A circle has the diameter equal to the length of the side of an equilateral triangle. What is the ratio of their respective areas?

A11 : 7 root 3

B22 : 7 root 3 ✓ Correct

C11 : 7 by root 3

D11 : root 3 by 3

Correct answer: (B) 22 : 7 root 3

Explanation

The ratio of areas is 22 : 7 root 3.

Let the side = diameter = a, so circle radius = a/2.

Circle area = pi x (a/2)^2 = pi x a^2 / 4.

Triangle area = (root 3 / 4) x a^2.

Ratio = pi : root 3 = 22/7 : root 3 = 22 : 7 root 3.

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