Question

Circle A has a diameter of 9 inches, a circumference of 28.26 inches, and an area of 63.585 square inches. The diameter of circle B is 5 inches, the circumference is 15.70 inches, and the area is 19.625 square inches.
Part A: Using the formula for circumference, solve for the value of pi for each circle.

Part B: Use the formula for area and solve for the value of pi for each circle.

Part C: What observation can you make about the value of pi for circles A and B?

Answer 1

Part A:
Circle A :   since Circumference=(pi)(Diameter)
 Subtstitute the info to the equation:
C=28.26 inches  d=9 inches

$c= (\pi ) (d ) 28.26= (9)(\pi) 28.26/9= (9/9)( \pi ) 3.14= \pi$  

Answer 2

Step-by-step explanation:

Given circle A

Diameter  = 9 inches

Circumference  = 25.26 inches

Area  = 63.585 square inches

Given Circle B

Diameter  = 5 inches

Circumference  = 15.70 inches

Area  = 19.625 square inches

A).  For circle  A,

Circumference of A, C = 2 x π x R

                              28.26 = 2 x π x ( D/2)

                               28.26 = 2 x π x ( 9/2)

                               28.26 = 2 x π x ( 4.5)

                                     π    = 3.14

  For circle B,

  Circumference of B, C = 2 x π x R

                              15.70 = 2 x π x ( 5/2)

                                15.70 = 2 x π x ( 5/2)

                               15.70 = 2 x π x ( 2.5)

                                     π    = 3.14

B). For Circle A

      Area of A, A = (π/4) x D x D

                       63.585 = (π/4) x 9 x 9

                              π    = 3.14

      For Circle B

      Area of B, A = (π/4) x D x D

                       19.625 = (π/4) x 5 x 5

                              π    = 3.14

C). The value of pi for both the circles A and B is same and is equal to 3.14