Question

Please help me please pleaee

Answer 1

a) 66cm. b) 50.28cm. or 50 2/7cm.

Explanation:

The circumference of a circle is C=2πr or C=πd.

π=22/7

a) C=πd

Plugin the diameter.

C=22/7 x 21

=66cm.

b) C=2πr

Plugin the radius.

C=2 x 22/7 x 8

=50.28cm. or 50 2/7cm.

Hope this helps :)

Answer 2

Hello,

A.i. the circumference of a circle is nothing else but its perimeter which formula is π × diameter = π × 2 × radius

Let π = 22/7 ≈ 3.142857, the egyptian approximation

Then if C is the circumference of the circle i., C = 22/7 × 21 = (22 × 21) / 7 = (22× 7×3 )/7 = 22 ×3 = 66 cm

ii. Applying the same formula for the second circle gives us C = 22/7 × 8 = 176/7 ≈ 25.14 meters, rounded to the nearest hundredth...

Good luck !