Question

Samantha’s rectangular gift is 10 inches. by 12 inches and is framed with a ribbon. She wants to use the same length of ribbon to frame a circular clock. What is the maximum radius of the circular clock? Round to the nearest whole number.

(JUSTIFY)

Answer 1

7 inches

Explanation:

The dimension of the rectangular gift is 10 by 12 inches so let us find the perimeter of this rectangle.

Perimeter of rectangular gift = 2 (L+ W) = 2 (10 +12) = 44 inches

Since we are to use the same length of ribbon to wrap a circular clock so the perimeter or circumference of the clock should be no more than 44 inches.

`2\pi r=44`

`r=(44)/(2\pi )`

`r=7.003`

Therefore, the maximum radius of the circular clock is 7 inches.

Answer 2

= 7 inches

Explanation:

The ribbon covers the perimeter of the gift.

Perimeter of a rectangle= 2L+2W

=2(12)+2(10)

=44 inches

If the same ribbon is used to frame a circular clock, the perimeter remains to be 44 inches.

Perimeter of a circle= 2πr where r is the radius of the circle.

44 inches= 2×π×r

r=44/2π

=7.0 inches

Radius of the circular clock is 7 inches