Question

On increasing the diameter of a circle by 40%, its area will be increased by (a) 40% (b) 80 % (c) 96 % (d) 82%

Answer 1

96%

Explanation:

let's assume the diameter of a circle is 10cm, so the area is 25π

now, lets increase the diameter by 40%. the diameter will become 14, and the area is 49π

Find the difference of the original circle and the one that is increased by 40%

49π - 25π = 24π

24π is what percent of 25π

(24π/25π) * 100 = 96%

Answer 2

whats the original diameter?