Question

on decresing the radius of the circle by 30%,its area is decreased by
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Answer 1

Answer:

51%

Step-by-step explanation:

Area = π r²

Let the radius of circle be ' x '

=> Area = π x²

Radius decreased by 30%

=> radius = x - 30%

=> radius = x - 30% ( x )

=> radius = x - 0.3x

=> radius = 0.7x

Area = π r²

=> Area = π ( 0.7x )²

=> Area = π 0.49x²

Area decreased by

=> π x² - π 0.49x²

=> π ( x² - 0.49x² )

=> π 0.51x²

Percentage

=> π 0.51x²/π x² * 100

=> 51%