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340fb804-8d8b-4040-a7af-ca856adaeceb
As shown in the figure, given the linear functions y = kx - b and y = $\frac{1}{3}$x intersect at point A(a, 1), then the solution for the equation $(k-\frac{1}{3})x = b$ is x =.
3
math
29c1d3e1-35d7-413f-9f83-b81ecf7ecb9d
A person is riding a bike on a road parallel to the tram tracks. He notices that a tram passes him from behind every 6 minutes and a tram passes him from the opposite direction every 2 minutes. Assuming the speeds of the trams and the person are constant (denoted as u$_{1}$ and u$_{2}$, respectively), please refer to the following diagram to find how often (in minutes, denoted as t) trams leave the station.
3
math
394169f4-8f13-44ef-8e47-0a4e2defaee3
There are several (more than 20) pieces of a naturally grown traditional Chinese medicine. From these, 20 pieces are randomly selected, and their weights are measured precisely in grams. It is specified that each piece of the medicine weighing no less than 15 grams is considered a high-quality product. The program flowchart shown below is used to count the number of high-quality products among the 20 samples, where $m$ represents the weight of each piece of medicine. The integers that should be filled in at points 1. and 2. in the chart are respectively.
14, 19
math
8b5b85e8-94db-4fbe-ba26-2ae449355978
As shown in the figure, the side length of rhombus ABCD is 3 cm, E is the midpoint of AB, and DE is perpendicular to AB. What is the area of rhombus ABCD in cm²?
$\frac{9\sqrt{3}}{2}$
math
45cf16fd-440e-47ed-a113-56de4e029ece
As shown in the figure, in △ABC, ∠C=90°, AC=3, AB=5, point D is a point on side BC. If △ACD is folded along AD, point C exactly lands on point E on AB, then BD=.
2.5
math
d6cc217c-163f-4546-b5e7-f140ca78898c
May 10th is Mother's Day. On Mother's Day, Xiaoming gave his mother 5 Carnations and 5 gift boxes. According to the information in the image, how much did Xiaoming spend in total?
440
math
e78191c2-89e7-47b4-9de0-066c68f9b2f0
Execute the program flowchart shown in the figure. If the input value of $n$ is $4$, then the output value of $s$ is.
$7$
math
d5d28b6b-433d-473d-94ef-32f98003be91
A workshop divides 10 workers into two groups, Group A and Group B, to process a certain type of part. The number of qualified parts processed by each worker in a unit of time is shown in the stem-and-leaf plot. It is known that the average number of qualified parts processed by the workers in both groups in a unit of time is 20, then m+n =
11
math
ffec0638-7dd9-45e8-94f4-de97ed9ed17f
Given: As shown in the figure, isosceles right triangles are constructed outward on the three sides of the right triangle ABC. If the hypotenuse AB = 3, then the area of the shaded part in the figure is.
4.5
math
134f6361-adfd-476c-ba22-f85fa5b53e7a
As shown in the figure, two bamboo poles AB and AD are leaning against the edge CE. It is measured that ∠ABC = α, ∠ADC = β. The ratio of the lengths of bamboo poles AB and AD is.
$\frac{\sin \beta }{\sin \alpha }$
math
aded07b5-ce35-41a6-ac7d-436ffdee5d62
In a physical education class, the PE teacher tested the standing long jump for 40 students in Grade 9, Class 1. The scores and the corresponding number of students are shown in the figure. What is the average score of this test?
$\frac{35}{4}$
math
76be66a2-1284-4f34-9da3-35c7ced55b4a
In the figure, in △ABC, DE∥BC, $\frac{DE}{BC}=\frac{2}{3}$, the area of △ADE is 8, then the area of △ABC is
18
math
cb6f75d0-f38e-4904-9a57-7d3b17c3e6b1
As shown in the figure, in △ABC, BP and CP are the angle bisectors of ∠ABC and ∠ACB, respectively, and PD ∥ AB, PE ∥ AC. The perimeter of △PDE is 6 cm. Then BC = ______ cm.
6
math
c0857def-714a-4466-8831-13e008ebacda
Given the following program, the output result is $$S=$$ ___.
$$56$$
math
c426dd60-e310-40ee-81ca-348fa76857ef
To understand the situation of teachers using multimedia for teaching at a school, a simple random sampling method was used to select 20 teachers from 200 teaching staff. The number of times they used multimedia for teaching last semester was surveyed and is represented in the stem-and-leaf plot shown in the figure. Based on this, it can be estimated that the number of teachers out of 200 who used multimedia for teaching between 15 and 30 times last semester is ___.
$$100$$
math
eb9c7348-8989-4dee-9da3-bfad25d8ba62
As shown in the figure, the radius of $$\odot O$$ is $$OC =\quantity{5}{cm}$$, the line $$l \perp OC $$, with the foot of the perpendicular at $$H$$, and $$l$$ intersects $$\odot O$$ at points $$A$$ and $$B$$, where $$AB=\quantity{8}{cm}$$. How many $$\unit{cm}$$ must $$l$$ be moved downward along the line of $$OC$$ to be tangent to $$\odot O$$?
$$2$$
math
6be44eb0-15d5-4a16-bff5-e6c430b10653
As shown in the figure, take two points $$C$$ and $$D$$ on the ray $$AB$$. How many rays are there in the figure?
$$4$$
math
9edbb849-2808-48f0-973a-af66c411c187
As shown in the figure, in rectangle $$ABCD$$, the length of $$AB$$ is $$a$$, and the length of $$BC$$ is $$b$$, where $$\dfrac{2}{3}b < a$$. The rectangular paper is folded in the following sequence, then the length of $$C'D'$$ is ___ (expressed in terms of $$a$$ and $$b$$).
$$3a-2b$$
math
94f1ca94-35fb-40e3-84cb-7d468b5bbafa
In the $$xOy$$ plane, consider the closed figure $$D$$ formed by the two semicircular arcs $$(x-1)^{2}+y^{2}=1(x \geqslant 1)$$ and $$(x-3)^{2}+y^{2}=1(x \geqslant 3)$$, and the two lines $$y=1$$ and $$y=-1$$, as shown in the shaded area in the figure. Let the solid of revolution formed by rotating $$D$$ around the $$y$$-axis be denoted as $$\Omega$$. If a horizontal cross-section of $$\Omega$$ at $$(0,y)(|y| \leqslant 1)$$ has an area of $$4 \pi \sqrt{1-y^{2}}+8 \pi$$, use Zu Geng's principle, a horizontally placed cylinder, and a rectangular prism to determine the volume of $$\Omega$$ as ___.
$$2 \pi ^{2}+16 \pi$$
math
74719e94-99a5-46ac-8465-a282b144db80
We can measure the distance to the Moon using the following method: as shown in the figure, during a full moon, place a 5-fen coin (with a diameter of about 2.4 cm) at a distance of about 2.6 meters from the eye (point O) at point AB, which exactly covers the Moon. Given that the diameter of the Moon is about 3500 kilometers, the distance between the Moon and the Earth is approximately ___ kilometers.
$$3.8\times 10^{5}$$
math
7cc7a71d-d0d8-4511-9526-aea55f17aee7
In the parallelogram $$ABCD$$, point $$E$$ is the midpoint of side $$AD$$. $$EC$$ intersects diagonal $$BD$$ at point $$F$$. Then, the ratio $$EF:FC$$ equals ___.
$$1:2$$
math
41d6f508-327f-4a49-9f5c-205b76cfdd80
As shown in the figure, in $$\triangle ABC$$, $$DE$$ is the perpendicular bisector of $$BC$$, with the foot of the perpendicular at $$E$$, and it intersects $$AC$$ at point $$D$$. If $$AB=6$$ and $$AC=9$$, then the perimeter of $$\triangle ABD$$ is ___.
$$15$$
math
aa5e4ece-ca75-40e3-8f3f-15e94c4d8583
To investigate the basic mathematical problem-solving abilities of students in a class, a random sample of students was taken to examine their scores on a mathematics test with a full score of 100 points. The score ranges were [45,55), [55,65), [65,75), [75,85), [85,95). The frequency distribution histogram is shown in the figure below. What is the average score of these students?
64
math
22b48c01-3a24-4b9d-88c1-5edffe73ff30
A marksman's score in rings, denoted as $$\xi$$, has the following distribution: Given that the expectation of $$\xi$$, $$E\xi=8.9$$, what is the value of $$y$$? ______.
0.4
math
6461cfb7-ea0e-4ecd-987a-7fbd00f9c115
During the large class break activities, students actively participate in physical exercises. Xiao Hong randomly selected a portion of students from the entire school to test their 'one-minute jump rope' performance and drew the partial frequency distribution histogram (divided into six groups from left to right, each group includes the minimum value but not the maximum value) and the pie chart as shown in the figure. If the number of 'one-minute jump rope' skips is no less than 130, the performance is considered excellent. The entire school has 1200 students. Based on the information provided in the figures, estimate the number of students in the school with excellent 'one-minute jump rope' performance.
480
math
b07eff77-7d96-4863-b847-5939761a6b02
As shown in the figure, lines $$AB$$ and $$CD$$ intersect line $$EF$$ at points $$E$$ and $$F$$, respectively, and $$∠1=105^{\circ}$$. When $$∠2=$$___, $$AB∥CD$$.
$$75^{\circ}$$
math
7d6bc469-7b1f-4c90-9d28-8ff93232761f
Use 6 different colors to color the 'smiley face' in the figure, with the requirement that the 'eyes' (i.e., the regions marked as $$A$$ and $$B$$ in the figure) use the same color. How many different ways are there to color it? (Answer with a number)
$$216$$
math
14f00ad8-85f0-47ce-93d6-5bd38e4384ea
As shown in the figure, the following geometric bodies are formed by arranging small cubes with an edge length of $$1$$ on the ground according to a certain pattern. If the exposed surfaces are all painted (the bottom surface is not painted), then in the $$n$$-th geometric body, the number of small cubes with only two faces painted is ___ .
$$(8n-4)$$
math
9dffc4a7-fe81-4382-8534-4120b93be070
The figure below shows the graphs of the functions: $$y=x^{2}-1$$, $$y=x^{2}+6x+8$$, $$y=x^{2}-6x+8$$, $$y=x^{2}-12x+35$$ in the same Cartesian coordinate system. The most likely graph for $$y=x^{2}-6x+8$$ is ___.
3
math
1ca36e5d-3747-4441-84ec-bd645c4dc760
As shown in the figure, the lines $$AD∥BE$$, $$AC$$ and $$BC$$ bisect $$∠BAD$$ and $$∠ABE$$ respectively, and $$∠CAD=55^{\circ}$$. Then $$∠CBE=$$ ___.
$$35^{\circ}$$
math
c42d89fc-592b-49d7-818c-50b894100e1f
As shown in the figure, $$A$$, $$B$$, and $$C$$ are three points on a number line (unit length is $$1$$), and the numbers they correspond to are all integers. If the number corresponding to point $$B$$ is $$7$$ more than twice the number corresponding to point $$A$$, then the number corresponding to point $$C$$ is ___.
$$3$$
math
367d9b97-a7a2-4305-a8c9-d1a9b9eda6e8
As shown in the figure, in rhombus $$ABCD$$, the diagonals $$AC$$ and $$BD$$ intersect at point $$O$$, and $$AC=8$$, $$BD=6$$. Then the height $$DH$$ of rhombus $$ABCD$$ is ___.
$$4.8$$
math
bbbc2f1a-3fc1-4f24-97a5-4f6bc47ad889
The top view of a geometric solid is a rectangle as shown in the figure, the front view (or main view) is an isosceles triangle with a base length of 8 and a height of 5, and the side view (or left view) is an isosceles triangle with a base length of 6 and a height of 5. The volume of the geometric solid is ______.
$$80$$
math
0dc0a891-8a05-4dd5-a861-9f75edb642f2
The chart below shows the scores of Xiao Hua's five math tests. The average score of Xiao Hua's five tests is ______.
92
math
bc6e7cdd-ea13-4c3d-9efb-db4b9c1b2f2d
A student walks to school, and in 10 minutes, he covers a part of the total distance (as shown in the figure). Estimating that he cannot arrive on time by walking, he switches to a taxi to reach the school. The relationship between his journey and time is shown in the following graph (the total distance is '1'). How many minutes earlier does he arrive at the school compared to if he had walked the entire way?
24
math
f2f3a696-df4c-4518-9e5b-15c0ad17ba58
As shown in the figure, it is known that $$\angle 1 = 34\degree$$, then $$\angle 2 =$$______.
56°
math
da168b9a-05ce-4e40-afca-dd801bb3390a
Two right-angled triangular rulers are placed with their right-angle vertices coinciding as shown in the figure. If $$∠AOD=110^{\circ}$$, then $$∠BOC=$$ ___.
$$70^{\circ}$$
math
f4387a69-ca69-46b1-8aa8-81875b61cc6b
As shown in the figure, a square ABCD with side length 4 is folded along the crease EF, such that point B lands on the midpoint G of side AD. The area of quadrilateral BCEF is ___.
6
math
6ce81a0e-4e76-45b8-94f1-aee2cd6b6c48
As shown in the figure, a residential area has a rectangular open space that is 30m long and 24m wide. It is planned to construct two identical rectangular green spaces within it, with their total area being 480m². There are pedestrian walkways of equal width between the two green spaces and around them. What is the width of the pedestrian walkway in meters?
2
math
ed44f172-0285-4b16-837e-ad6528d52533
As shown in the figure, line $$AD \parallel BE$$, $$AC$$ and $$BC$$ bisect $$\angle BAD$$ and $$\angle ABE$$ respectively, and $$\angle CAD = 55^{°}$$. What is $$\angle CBE =$$ ___.
$$35^{\circ}$$
math
1d4b895c-a57c-4475-82b7-d10e597e2ef9
As shown in the figure, draw the perpendicular bisector of line segment $$AB$$, intersecting $$AB$$ at point $$O$$. On this perpendicular bisector, intercept $$OC = OA$$. With point $$A$$ as the center and the length of $$CA$$ as the radius, draw an arc intersecting $$AB$$ at point $$P$$. The ratio of $$AP$$ to $$AB$$ is ___.
$$\dfrac{\sqrt{2}}{2}$$
math
84c34316-9b90-430c-985e-a64c2247ec34
As shown in the figure, a rectangle is cut into four pieces along the dotted lines (where $$x>y$$). These four pieces can be exactly assembled into a square. If $$y=2$$, then the value of $$x$$ is ___.
$$1+\sqrt{5}$$
math
74d0eab7-a761-488e-bf98-9693e5b8fc2f
In the semicircle shown in the figure, $$AD$$ is the diameter, and $$AD=3$$, $$AC=2$$. The value of $$\sin B$$ is ___.
$$\dfrac{2}{3}$$
math
7accc25d-fbc2-4e2b-b386-fbefac985d2b
As shown in the figure, in rectangle $$ABCD$$, $$M$$ and $$N$$ are the midpoints of sides $$AD$$ and $$BC$$, respectively, and $$E$$ and $$F$$ are the midpoints of segments $$BM$$ and $$CM$$, respectively. If $$AB=8$$ and $$AD=12$$, then the perimeter of quadrilateral $$ENFM$$ is ______.
$$20$$
math
718b11ad-6569-4765-b3e4-4ce81c3fa842
In the figure, ▱ABCD has EF passing through the intersection point O of the diagonals. If AB = 4 cm, AD = 3 cm, and OF = 1 cm, then the perimeter of quadrilateral BCFE is ______.
9cm
math
dce43017-d982-44d3-b4cb-a927aead82a0
According to the 'Thresholds and Testing for Blood and Breath Alcohol Content for Vehicle Drivers' released by the General Administration of Quality Supervision, Inspection and Quarantine, the thresholds for blood alcohol content for drivers after drinking or being drunk are shown in Table 1. The traffic law enforcement department of a certain region has compiled the law enforcement record data for May, as shown in Table 2. The estimated probability of driving after drinking in this region in May is ___.
$$0.09$$
math
f2e43b91-a789-4569-8692-46ff42152ac8
From a physical fitness test involving 400 participants, the scores of 50 randomly selected individuals are summarized in the following table. The estimated variance of the scores for the 400 participants is ___.
1.16
math
45b103c6-0dfa-48cd-b776-e0d67cbb53ed
The swimming ring we use when swimming can be considered as formed by rotating the following shape ___ (fill in the number) around its axis of symmetry.
3
math
0b0608ec-e8de-45dc-9404-be5c5e9b3ba1
As shown in the figure, in the Cartesian coordinate system, △P$_{1}$OA$_{1}$, △P$_{2}$A$_{1}$A$_{2}$, △P$_{3}$A$_{2}$A$_{3}$, ... are all isosceles right triangles, with their right-angle vertices P$_{1}$(3,3), P$_{2}$, P$_{3}$, ... all lying on the line y = -$\frac{1}{3}$x + 4. Let the areas of △P$_{1}$OA$_{1}$, △P$_{2}$A$_{1}$A$_{2}$, △P$_{3}$A$_{2}$A$_{3}$, ... be S$_{1}$, S$_{2}$, S$_{3}$, ..., respectively. According to the pattern reflected in the figure, S$_{2018}$ =.
$\frac{9}{{{4}^{2017}}}$
math
8dd77802-5e7d-4bdd-a3ad-2865a52510d4
The right table gives a 'triangular number array', where each column forms an arithmetic sequence, and from the third row onwards, each row forms a geometric sequence. Let the number in the $i$th row and $j$th column be ${{a}_{ij}}(i\ge j,i,j\in {{N}^{*}})$, then ${{a}_{mn}}=$$(m\ge 3)$.
$\frac{m}{{{2}^{n+1}}}$
math
52691b9d-f705-403c-9b93-584e88ec072b
In the figure, in rectangle $ABCD$, $AB=1$, $BC=\sqrt{3}$. A circle is drawn with $B$ as the center and $BD$ as the radius, intersecting the extension of $BC$ at point $M$. Another circle is drawn with $D$ as the center and $CD$ as the radius, intersecting $AD$ at point $N$. The area of the shaded region in the figure is.
$\frac{7\pi }{12}-\frac{\sqrt{3}}{2}$
math
751d4fa6-4dfd-4b49-a9af-8091001b7d93
In the Pascal's Triangle, replace each number with a fraction to form a fraction triangle known as the Leibniz Triangle, as shown in the figure. If an ordered pair of real numbers (m, n) represents the nth number from the left in the mth row, such as (4, 2) representing the fraction $\frac{1}{12}$, then the fraction represented by (8, 2) is.
$\frac{1}{56}.$
math
b40dbb22-d872-4ce6-a2c7-a3bec3493a86
The relationship between the quantity of bananas sold (in kilograms) and the selling price (in yuan) at a fruit shop is shown in the following table: If the quantity of bananas sold is represented by x (kilograms) and the selling price by y (yuan), then the relationship between y and x is;
y=3x
math
c8ecb5ab-17f7-4726-b12e-16f0ca0a059c
As shown in the figure, in rectangle ABCD, DE is perpendicular to AC at E, and ∠ADE:∠EDC = 3:2. What is the measure of ∠BDE?
18°
math
736e103b-f7eb-45d1-abad-e87bdceb5c9a
Cities A and B are 600 kilometers apart. Two cars, Car A and Car B, start from City A and drive towards City B at the same time. Car A, after reaching City B, immediately returns and meets Car B on its way back. The graph below shows the distance $y$ (km) from City A and the driving time $x$ (h) for both cars. When they have been driving for 7 hours, the two cars meet. What is the speed of Car B?
75 km/h
math
951aef9f-fc04-4abc-a0bb-03f5fb9bddac
As shown in the figure, person 甲 starts from point $A$ and walks in a direction $70{}^\circ $ north of east to point $B$, while person 乙 starts from point $A$ and walks in a direction $15{}^\circ $ south of west to point $C$. The degree measure of $\angle BAC$ is.
$125{}^\circ $
math
486d489d-d67e-4fcf-945d-398d4ec4d8e1
As shown in the figure, several squares with patterns and without patterns, all of the same size, are combined to form a regular pattern. It is known that the side length of each small square is $0.3m$. Please express the relationship between the number of squares with patterns $n$ and the length of the pattern ${{L}_{n}}$ using an algebraic expression.
${{L}_{n}}=0.3(2n+1)$
math
600e60fe-03e5-4ed2-9ee1-31b78b6bccc2
As shown in the figure, in rectangle $ABCD$, $AB=10$, $AD=6$, and $E$ is a point on $BC$. When $\Delta CDE$ is folded along $DE$, point $C$ lands on point $F$ on $AB$. Find the length of $CE$.
$\frac{10}{3}$
math
20c655f6-649a-40c1-9b4a-ceb33fb65e57
As shown in the figure, there are four points $$A$$, $$B$$, $$C$$, and $$D$$ on the number line. The point representing the opposite number of $$2$$ is point ___.
$$A$$
math
10cbfb04-2b11-4fc1-b8c1-1402996ece1b
As shown in the figure, in $$\triangle ABC$$, $$AB=2$$, $$BC=1.5$$, $$\angle ABC=120^{\circ}$$, if $$\triangle ABC$$ is rotated around the line $$BC$$ for one full revolution, then the volume of the resulting solid of revolution is ___.
$$\dfrac{3 \pi }{2}$$
math
47115a04-0840-4af8-8e8d-ab0fb238f0be
Let the universal set $U=\mathbb{R}$, $A=\{x\in \mathbb{N} | 1 \le x \le 10\}$, $B=\{x\in \mathbb{R} | x^2 + x - 6 = 0\}$. Then the set represented by the shaded area in the following figure is:
$\{2\}$
math
57abbf22-8a73-4f90-90fe-851bc392d3b8
As shown in the figure, the lengths of the two diagonals of rhombus $$ABCD$$ are $$AC=8$$ and $$BD=6$$, respectively. Therefore, the area of rhombus $$ABCD$$ is ___.
$$24$$
math
44276b2c-df5e-4c59-a61b-0fb62132752c
Below is a simple numerical operation program. When the input value of $x$ is 4, the output value is.
2
math
045d621e-a814-4806-8de0-b5ba10f6d18b
As shown in the figure, in the complex plane, the complex number corresponding to point A is z, then the complex number z = ___.
2-i
math
f4a47afd-9713-460c-bef8-f3e4de60dcd0
As shown in the figure, $$AD$$ is the median of $$\triangle ABC$$, $$AB > AC$$, $$AB = 8\unit{cm}$$, and the difference in the perimeters of $$\triangle ABD$$ and $$\triangle ACD$$ is $$2\unit{cm}$$, then $$AC = $$___$$\unit{cm}$.
$$6$$
math
c4f3ce75-621a-486c-b94b-1e88684be70d
As shown in the figure, a line parallel to $$BC$$, $$DE$$, divides $$\triangle ABC$$ into two parts of equal area. What is the value of $$\dfrac{AD}{AB}$$?
$$\dfrac{\sqrt{2}}{2}$$
math
567bb63d-fd8e-4ae0-bee3-ae9b06a5926d
A company has three factories producing the same type of electronic product. The production distribution of the three factories is shown in the figure. Now, using stratified sampling, 100 items are to be drawn from the products of the three factories for a lifespan test. The number of items that should be drawn from the first factory is ___. The test results show that the average lifespan of the products from the first, second, and third factories are 1020 hours, 980 hours, and 1030 hours, respectively. Estimate the average lifespan of the products produced by this company to be ___ hours.
50 1015
math
1e3d56aa-130b-4ebe-91c8-c6070529c4bd
The flowchart of a program is shown in the figure. After the program runs, the output value of $$x$$ is $$31$$. Then, $$a$$ equals ______.
$$3$$
math
3c966eb6-2736-44d9-be16-e97e44049a2e
A clothing mall conducted a study to understand the relationship between the monthly sales volume of sweaters $$y$$ (pieces) and the average monthly temperature $$x$$ ($$\degree{\rm C}$$). They randomly collected data on the monthly sales volume and the average temperature for four months, as shown in the table below: From the data in the table, the linear regression equation $${\mathstrut{\hat y}}={\mathstrut{\hat b}}x+{\mathstrut{\hat a}}$$ was calculated, where $${\mathstrut{\hat b}}\approx-2$$. The meteorological department predicts that the average temperature for the next month will be about $$6\degree{\rm C}$$. Based on this statistical data, the estimated sales volume of sweaters for the next month is ______ pieces.
$$46$$
math
610fa059-ba68-4a94-8000-42e4fae60d90
As shown in the figure, if the front view of a cone is an isosceles right triangle with a hypotenuse of length $$4$$, then the lateral surface area of the cone is ___.
$$4\sqrt{2} \pi$$
math
03d4ef55-5bc6-4240-8bae-468166d7925a
In an opaque bag, there are $$n$$ balls that are identical except for their color, including $$5$$ black balls. A ball is randomly drawn from the bag, its color is noted, which is called one ball-drawing trial, and then it is put back into the bag. The bag is mixed again, and another ball is drawn. Below is a table of the number of ball-drawing trials and the number of times a black ball was drawn, simulated using a computer: According to the table, the estimated value of $$n$$ is ___.
$$10$$
math
0ff2d417-783f-424d-a108-60e027d9bd9e
As shown in the figure, in the right triangle $$\text{Rt}\triangle ABC$$, $$∠C=90^{°}$$, $$BC=3$$, $$AC=6$$, point $$D$$ is a moving point on the side $$AC$$, and point $$D$$ moves from point $$C$$ to point $$A$$. If $$CD=x$$ and the area of $$\triangle ABD$$ is $$y$$, then the relationship between $$y$$ and $$x$$ is ___. (No need to specify the range of $$x$$)
$$y=9 -\dfrac{3}{2}x$$
math
cb6bc8c7-b39e-45ef-915b-e89a322ac547
As shown in the figure, $$\triangle ABC \cong \triangle DEF$$, $$AD = 10\ \unit{cm}$$, $$BE = 6\ \unit{cm}$$, then the length of $$AE$$ is ___.
$$\quantity{2}{cm}$$
math
0988cba8-e436-4cb4-9789-7f1c8482d8a7
Two masts on a ship, each 7.5m high, are 15m apart. A 30m long rope is tied to the tops of the masts and is stretched as shown in the figure. Assuming the rope lies in the plane containing the two masts, the distance from the point P where the rope touches the deck to mast AB is ___ m.
4.75
math
61824613-d34b-499c-89e4-63400179e5ed
As shown in the figure, in $$\triangle ABC$$, point $$D$$ is on side $$BC$$, $$AD \bot AC$$, $$\sin\angle BAC = \dfrac{2\sqrt{2}}{3}$$, $$AB = 3\sqrt{2}$$, $$AD = 3$$, then the length of $$BD$$ is ___.
$$\sqrt{3}$$
math
729b2a9c-e708-47d1-82a1-41be61d53e27
As shown in the figure, in the rhombus $$ABCD$$, $$AB=10$$, $$AC=12$$, then its area is ___.
$$96$$
math
96ef0f0f-963c-485c-b645-c2155cfd1319
As shown in the figure, this is a cross-section of a water pipe with a diameter of $$2m$$ laid horizontally. The width of the water surface is $$1.6m$$. The deepest point of the water in the pipe at this time is ___$$m$$.
$$0.4$$
math
428b3aff-1aaf-4f6a-94ad-e1fde3b89682
The English oral test scores (unit: points) of 10 students in groups $$A$$ and $$B$$ are as follows: Group $$A$$: $$82$$, $$84$$, $$85$$, $$89$$, $$79$$, $$80$$, $$91$$, $$89$$, $$79$$, $$74$$; Group $$B$$: $$76$$, $$90$$, $$84$$, $$86$$, $$81$$, $$87$$, $$86$$, $$82$$, $$85$$, $$83$$. The scores of the two groups are represented in a stem-and-leaf plot (as shown in the figure). The scores of group ___ are more consistent.
$$B$$
math
8a5f5d30-0069-4b93-bd5d-752c9e9c2c16
As shown in the figure, given that $$O$$ is the origin, point $$A\left (3,0\right )$$, $$B\left (4,4\right )$$, and $$C\left (2,1\right )$$, the coordinates of the intersection point $$P$$ of $$AC$$ and $$OB$$ are ___.
$$\left (\dfrac{3}{2},\dfrac{3}{2} \right )$$
math
cbf67581-a84e-4488-bb83-9af322c2e554
According to the program shown in the figure, the output value of $$k$$ is ___.
$$3$$
math
5d710ccf-bc87-443d-af72-c3dcfd246b95
Draw a square, then connect the midpoints of each side of this square to form a second square, and so on. In this way, a total of 3 squares are drawn, as shown in the figure. If a point is randomly thrown into the figure, what is the probability that the point lands inside the third square?
$$\dfrac{1}{4}$$
math
28d2dcaa-de76-476b-96a5-72682dac6b4b
As shown in the figure, given points $$A(a,0,0)$$, $$B(0,b,0)$$, $$C(0,0,c)$$, then a normal vector of plane $$ABC$$ is ___.
$$(bc,ac,ab)$$
math
01fb4f15-6f38-4b4e-8186-7b0d778706a2
As shown in the figure, in the tetrahedron $$C-ABD$$, $$E$$ and $$F$$ are the midpoints of $$AC$$ and $$BD$$ respectively. If $$CD=2AB=4$$ and $$EF \bot AB$$, then the angle formed by $$EF$$ and $$CD$$ is ___.
$$30^{\circ}$$
math
b0702489-0f31-47f8-afe9-5a415d47db64
The figure below shows a simple numerical operation program. When the input value of $$x$$ is $$-1$$, the output value is ___.
$$-2$$
math
2211f64e-0747-41b4-9ebe-a756414c224c
A factory conducts a sampling inspection of a batch of products. Based on the net weight (unit: grams) data of the inspected products, a frequency distribution histogram is drawn as shown in the figure. It is known that the range of the product's net weight is $$[96,106]$$, and the number of products with a net weight in the range $$[96,100)$$ is $$24$$. The number of products with a net weight in the range $$[98,104)$$ in the sample is ______.
$$60$$
math
abbd794a-88ff-417b-bf60-e4066864cd15
In the right triangle $$ABC$$, $$\angle B=90^{\circ}$$, the perpendicular bisector of $$AC$$, $$DE$$, intersects $$AC$$ at point $$D$$ and $$BC$$ at point $$E$$. If $$\angle BAE=10^{\circ}$$, then the measure of $$\angle C$$ is ___.
$$40^{\circ}$$
math
c1854fd1-2739-4a9f-9d51-0d1a46ba5847
To welcome the school arts festival, a class in the seventh grade is holding a class song collection activity, with submissions accepted from Monday to Friday. The class committee grouped the number of works submitted by the students by day and created a frequency distribution histogram as shown in the figure. It is known that the ratio of the heights of the rectangles from left to right is $$2:3:4:6:1$$, and the frequency of the second group is $$9$$. How many works were submitted by the whole class?
$$48$$
math
1a5ef5aa-5f8a-42b7-97f2-760c01a23b0a
In the stem-and-leaf plot shown, the sum of the medians of Group A and Group B is
64
math
fd2a02c7-a718-4094-bf13-53696a21998d
As shown in the figure, $$\triangle ABC$$ is an equilateral triangle, and $$BM=CN$$. $$AM$$ and $$BN$$ intersect at point $$P$$. The measure of $$\angle APN$$ is ______ degrees.
60
math
403e26ad-d25d-420c-a48b-602fa1f00779
As shown in the figure, extend line segment $$AB$$ to $$C$$, such that $$BC=4$$. If $$AB=8$$, then the length of line segment $$AC$$ is ___ times the length of $$BC$$.
$$3$$
math
5f137a38-61d1-4843-b54b-298d16173882
The graph of the function $$y=f(x)=a^{x}-\dfrac{1}{a}$$ (where $$a>0$$ and $$a \neq 1$$) could be ___.
4
math
df698860-1445-4fb5-bb12-89c595e5cfa7
As shown in the figure, given the hyperbola $$\dfrac{x^2}{a^2}-\dfrac{y^2}{b^2}=1(a>0,b>0)$$ with the left focus at $$F_1$$, the left and right vertices at $$A$$ and $$B$$ respectively, and point $$M$$ on the hyperbola and above the $$x$$-axis, $$MF_1⊥x$$-axis. The lines $$MA$$ and $$MB$$ intersect the $$y$$-axis at points $$P$$ and $$Q$$ respectively. If $$|OP|=\sqrt{2}|OQ|$$, then the eccentricity of the hyperbola $$e=$$ ___.
$$3+2\sqrt{2}$$
math
a65d00e4-aef0-44f1-bbc0-6488bcb017d2
The figure below is a flowchart of an algorithm. Answer the following question: When the input value is $$3$$, the output result is ___.
$$8$$
math
44cd4307-b724-402e-a471-4b0f5787a7f5
As shown in the figure, regular octagons with side lengths of $$1$$, $$2$$, and $$3$$ are stacked together, with the distance between adjacent beads on the same side being $$1$$. If regular octagons with side lengths of $$4$$, $$5$$, $$6$$, $$\cdots$$, $$10$$ are placed in the same manner, then the total number of beads in the tessellation of these $$10$$ regular octagons is ___.
$$341$$
math
6df9187b-c38e-44ce-b414-cf60f19772c5
As shown in the figure, in $$\triangle ABC$$, it is given that $$\overrightarrow{AN}=\dfrac{1}{2}\overrightarrow{AC}$$, and $$P$$ is a point on $$BN$$. If $$\overrightarrow{AP}=m\overrightarrow{AB}+\dfrac{1}{4}\overrightarrow{AC}$$, then the value of the real number $$m$$ is ___.
$$\dfrac{1}{2}$$
math
b904c107-0276-4fe6-8700-451c8d00a19a
As shown in the figure, $$\triangle ABC$$ is an equilateral triangle with a side length of $$2\sqrt{3}$$, and $$P$$ is any point on the circle centered at $$C$$ with a radius of $$1$$. Then, $$\left (\overrightarrow{AP}\cdot \overrightarrow{BP}\right )_{ \min }=$$ ___.
$$1$$
math
f9eb7ea9-debb-4031-a02a-dce5ac5c0b36
The graph shown is of the inverse proportion function $y=\frac{k}{x}$ in the second quadrant. If the area of rectangle OABC in the graph is 2, then k=.
-2
math
ec216eff-611e-4d88-bbbb-09a0f869750c
As shown in the figure, the light bulb $P$ is directly above the horizontal rod $AB$. The shadow of $AB$ under the light is $CD$, and $AB \parallel CD$. Given that $AB = 1.5m$, $CD = 4.5m$, and the distance from point $P$ to $CD$ is $2.7m$, what is the distance between $AB$ and $CD$ in meters?
$1.8$
math
3b62e521-79c4-4c66-b9d6-6864d014e96b
As shown in the figure, in rectangle ABCD, DC = 6 cm. There is a point E on DC. Folding triangle ADE along line AE makes point D fall exactly on side BC, and this point is labeled as F. If the area of triangle ABF is 24, then the length of CE is cm².
$\frac{8}{3}$
math
9c5cb87d-67f7-43e6-b143-6c52fd2effb2
As shown in the figure, a right-angled triangular board ABC with a ${30}^\circ$ angle is rotated around point A, so that points B, A, and C′ lie on the same straight line. The angle of rotation of the triangular board ABC is _____ degrees.
150°
math