A teacher would like to estimate the percentage of her students who play chess.

Which method should the teacher use to select the sample?


A. select all students who are currently in the chess club

B. use a computer to randomly select 30 student IDs from all her students

C. use a computer to randomly select 30 student IDs from all students

D. select every other student in her classes until she has selected a total of 30 students

Answer:

Surface area = 136 cm²    Volume = 80cm³

Step-by-step explanation:

Surface Area = face 1 + face 2 + face 3 + face 4+ face 5 + face 6

SA = 2(4) + 2(4) + 2(10) + 2(10) + 4(10) + 4(10)

SA = 8 + 8 + 20 + 20 + 40 + 40

SA = 16 + 40 + 80

SA = 136

----------------------

Volume = l*w*h

Volume = 4*2*10

Volume = 8*10

Volume = 80

Answer:

4

Step-by-step explanation:

*

Answer:

3.375

Step-by-step explanation:

divide 3/8 and you get 0.375 then add 3 and you get 3.375

Answer:

90 square kilometers

Step-by-step explanation:

1. split the figure in small definite sections

2. find the areas of the smaller sections.

3. find the sum of the areas.

Answer: The total surface area is 633.9

Step-by-step explanation:

12.25 times 15.75, then divide by 2 = 96.46875 (this is the area of the triangle

Then times 4 = 385.875 (Because there are four triangles

15.75 times 15.75 = 248.0625 (The area of the square)

The sum is 633.9375

Rounded = 633.9

Answer:

C = 2 pi r, so diameter is 40!

Step-by-step explanation

125.6 = 2 pi r

125.6 divided by 2 is 62.8.

Now its, 62.8 = pi times r

62.8/3.14 = 20.

r = 20

but this is the radius so the diameter is 2 times for than the radius. 20 x 2 = 40

Answer: it's A

Step-by-step explanation:

since the cost for hiring a plumber for three hours costs $120 so in graph A the graph has more likely stopped at $120 on the y axis which can be said as the cost axis too. I'm pretty sure the answer is A!

Answer: y = 1/5x + 2

Check out the workings I have done in the document I have uploaded :)

Answer:

1 3 4 5 6 7 8 10

Step-by-step explanation:

the numbers 7,8,9,0 represent 8th graders and the groups 1 3 4 5 6 7 8 10 all contain at least one of the numbers while the others groups dont meaning they are no 8th graders in groups 2 or 9

Answer:

If I am correct, I think the surface area is 448.

Step-by-step explanation:

First start by finding the area of all the sides

Front side. 12 x 10 = 120

2 triangle sides: 8 x 10 = 80, 80 x 2 = 160

Bottom side: 6 x 12 = 72

Back side: 8 x 12 = 96

Then add up the surface area

120 + 160 + 72 + 96 = 448

Btw I don't know if I am correct, but I think this is the way you find surface area.

Answer:

x=-8.5

Step-by-step explanation:

Combine like terms:

9+8=-4x+2x

Solve:

17=-2x

Divide:

17/-2=x

-8.5=x

Hope this Helps!

Answer:

your answer is x=-8.5

Step-by-step explanation:

Answer:

Hi,

Step-by-step explanation:

Let say a the base of the triangle A and b the base of the triangle B.

[tex]a)\\\left\{\begin{array}{ccc}\dfrac{a*x}{2}&=&30\\\dfrac{b*(x+3)}{2}&=&32\\b=a-4\\\end{arraqy}\right.\\\\(i): a=\dfrac{60}{x}\\\\(ii): b=\dfrac{64}{x+3}\\\\b)\\\dfrac{64}{x+3}=\dfrac{60}{x}-4\\\\64x=(60-4x)*(x+3)\\\\4x^2+16x-180=0\\\\x^2+4x-45=0\\\\\Delta=16+4*45=196=14^2\\x=\dfrac{-4+14}{2}=5\ or\ x=\dfrac{-4-14}{2}=-9\ (impossible)\\So\ x=5,\ a=\dfrac{60}{5}=12, b=\dfrac{64}{5+3}=8\\\\Area\ of\ A=12*5/2=30\\Area\ of\ B=8*8/2=32\\\\Height\ of\ triangle\ B=x+3=5+3=8.\\[/tex]

Answer:

Complementary Angles

Step-by-step explanation:

They are both in right angles

Answer:

132

Step-by-step explanation:

No way you can find the whole area with one solution. So we have to go by each shape.

Let's start with the triangle on top, only one part of it. We know that half of the base is 3. We could go long and hard and use the pythagorean theorem and then repeat that 8 times. Instead, you can imagine moving the 2 triangles into a rectangle. Now you have a rectangle that is 3x4 inches. Repeat 4 times for each of the triangles. Then just the square which is 6x6. Add them and bam!

Answer: x=15

Step-by-step explanation:

x/3+1= 6

Step 1: Subtract 1 from both sides (always do inverse operations with the number, not the x term(s))

x/3 + 1-1 = 6-1

x/3= 5

Step 2: Now we need to isolate x (get it on its own). To do this, we must move the 3 to the other side, which we will do by multiplying the 3 and the 5 (as since the 3 was used for divisision, its inverse operation is multiplication).

x/3 = 5

x = 5x3

x= 15

Step 3: Check by using PITA, or "Plugging In the Answers"

We came to the conclusion that x=15. Now, we can "plug in", or substitute the x in the equation for 15:

x/3 + 1= 6

15/3 + 1= 6

5+ 1= 6

6=6

Correct ✔️

Answer:

X = 24

Step-by-step explanation:

3 + 1 = 4

X/4 = 6

Multiply both sides by 4

X = 24

Answer:

Step-by-step explanation:
First, you would want to subtract the 3 on the left side to the right side to get the 1/5x to be alone.
1/5x>6
Next, we need to solve for x, by multiplying 5 to cancel out the 1/5.
(5)1/5x>6(5)
That leaves us with x>30
treat the inequality sign as an equal sign, that should help

Answer: adjacent and complimentary

Step-by-step explanation:

adjacent because they are next to each other and complimentary because they together make 90 degrees

Answer:

The answers are B and D, I did this one.

Yw guys

Answer:

5) Y = 144

Step-by-step explanation:

[tex]\frac{Y}{1.8} = 80[/tex]

Bring 1.8 from the numerator to the denominator and change the sign from divide to multiply. Also, the 1.8 switches sides so the equation looks like:

Y = 80*1.8

Y = 144

Hence, Y is equal to 144.

Hope this helps!!!

Please mark me as brainliest!!!

Answer: x = 9

Angle B = 40

Step-by-step explanation:

5x-5 = 3x+13 Those angles are the same, they are corresponding angles

5x = 3x + 18 Solve the equation

2x = 18

x = 9

3(9)+13 Solve it

Angle B = 40

Hope this helps.

Answer:

none of those

Step-by-step explanation:

A trapezoid is a 4-sided shape with 1 parallel side

Could you pls choose this as brainliest???!!!

It is equal. The same either way. :)

Hey there!

PROBLEM #1. 4 * 2,160

4 * 2,160
= 2,160 * 4

= 2,160 + 2,160 + 2,160 + 2,160

= 4,320 + 4,320

= 8,640
Therefore, the answer should be: 8,640

Problem #2. 4 * 2,610
4 * 2,610
= 2,610 * 4

= 2,610 + 2,610 + 2,610 + 2,610

= 5,220 + 5,220

= 10,440

Therefore, the answer should be:

10,440

Good luck on your assignment & enjoy your day!

~Amphitrite1040:)

Answer:

y=bh

Step-by-step explanation:

Answer:

2÷1 =2

2x1 =2

2-1 = 1

Step-by-step explanation:

Hopw this helps

Answer:

The answer would be 7 dollars.

Step-by-step explanation:

Hope this helps!

Answer:

$7

Step-by-step explanation:

84 divided by 12 is 7 so it would be 7 dollars