Question

Can someone please help me? if you can explain please...

A dinner plate has a diameter of 7 inches. Approximately how many inches is the circumference of the plate?

A. 14 inches

B. 22 inches

C. 44 inches

D. 154 inches

The diameter of Jacob’s circular tabletop is 6 feet. What is the area, in square feet, of Jacob’s tabletop?

A. 6π

B. 9π

C. 12π

D. 36π

Sarah builds a dollhouse. The floor of the dollhouse is square. Sarah covers the floor with 144 square inches of tile. How long, in inches, is one side of the dollhouse floor?

A. 12

B. 38

C. 72

D. 144

Answer 1

C= pi•diameter. If the dinner plate's diameter is 7 inches, then multiply 7 times pi, 3.14. 7•3.14= 21.98. So, the answer for the first question is B, 22. :) 

For the second question, it is asking for the answer in terms of pi. Since the diameter is 6, divide 6 by 2 to get the radius. (A=pi•radius squared) 6 divided by 2 is 3. Now, square 3. which gives you 9. Since the answer has to be in terms of pi, the answer is B. ;) 

Answer 2

Question 1:
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Given information
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Diameter = 7 inches

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Find Circumference
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Circumference = πD
Circumference = π x 7
Circumference = 22 inches (nearest inches)

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Answer: 22 inches
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Question 2:
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Find Radius
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Diameter = 6 feet
Radius = 6 ÷ 2
Radius = 3 feet

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Find Area
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Area = πr²
Area = π x 3 x 3 
Area = 9π ft²

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Answer: 9π ft² (Answer B)
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Question 3:

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Given information
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Area = 144 in²

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Formula
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Area of Square = Length x Length

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Apply Formula
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144 = Length x Length
Length² = 144
Length = √144
Length = 12

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Answer : 12 inches (Answer A)
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