Question

Find the radius of a circle whose circumference is 31.4 centimeters. Approximate pi as 3.14.

Answer 1

`5\:\mathrm{cm}`

Explanation:

The circumference of a circle is given by
`C=2\pi r`, where
`r` is the radius of the circle.

What we're given:

• 
  `C` of 31.4

Solving for
`r`:

`31.4=2\cdot 3.14 \cdot r,\\r=(31.4)/(2\cdot 3.14)=\boxed{5}`

Answer 2

Radius of circle is 5 cm.

Explanation:

Given that

• Circumference of circle = 31.4 cm
• Using value of π = 3.14

To Find :-

Radius of circle

Formula Used

Circumference of circle = 2 × π × r

Solution :-

Using Formula

Circumference of circle = 2 × π × r

Substitute the values into the formula

31.4 cm = 2 × 3.14 × r

multiply

31.4 cm = 6.28 × r

Divide , we get

31.4 cm /6.28 = r

5 cm = r

Hence, Radius of circle is 5 cm.