Question

Use pie=3.14 to estimate the unknown measures for each circle.c=132 ind=r=A=I'll upload a picture

Answer 1

Problem N 25

we know that

C=132 in

Remember that

The formula to calculate the circumference is given by

`C=pi*D`

using pi=3.14

C=132 in

substitute given values in the formula

`\begin{gathered} 132=3.14*D \\ solve\text{ for D} \\ D=(132)/(3.14) \\ D=42.04\text{ in} \end{gathered}`

The diameter D=42.04 in ( with pi=22/7 the diameter is 42 in exact)

Find out the radius r

r=D/2=42.04/2=21.02 in -----> the radius is half the diameter

Find out the area of the circle

The area is given by the formula

`A=pi*r^2`

we have

r=21.02 in

pi=3.14

substitute

`\begin{gathered} A=3.14*21.02^2 \\ A=1,387.38\text{ in}^2 \end{gathered}`

therefore

the answer is

d=42.04 in

r=21.02 in

A=1,387.38 in2