Question

1. Radius of a playground was reduced by 20% of the initial radius. If initially radius of the playground was 35 meter. Then what percentage of the original area will be left?​

Answer 1

Answer:

Initial area=π35^2

Reduced area=π×(35×0.8)^2. [(100-20)/100=0.8]

% of area left with respect to original area=

[{π.35^2-π(35×0.8)^2}/(π35^2)]×100

=[(63×7)/(35×35)]×100

=36%