Question

MARKING BRAINLIST! PLEASE HELP!

Answer 1

Answer:

$\boxed {\boxed {\sf C. \ 4 \ inches}}$

Step-by-step explanation:

Circumference is the perimeter of a circle. It can be found using the formula:

$c= \pi d$

However, we are given the radius.

• The radius measures from the center to the edge of the circle.
• The diameter measures from edge to edge through the center.
• So, the diameter is twice the radius, or d=2r

The formula can be rewritten as:

$c= \pi 2 r$

We know the circumference is 25.12 inches.

$25.12 \ in = \pi 2r$

Let's round pi to 3.14

$25.12 \ in = (3.14) 2r$

We want to solve for the radius, so we must isolate it.

Divide both sides by 3.14 because the inverse of multiplication is division.

$25.12 \ in / 3.14= (3.14 ) 2r / 3.14$

$8 \ in = 2r$

Divide both sides by 2.

$8 \ in / 2 = 2r/2$

$4 \ in = r$

The radius of the disc is 4 inches.