Question

parameter of a circle is reduced by 50% then reduce by area will be.....

Answer 1

let it do by effective %

here decrease in parameter = 50 %

there is decrease in paremeter then obviously it's area will be decreased , take a = -50 ,b = -50

% change in area = a + b + ab /100

= -50 - 50 +(-50) (-50 ) /100

= -100 + 2500 /100

= -100 + 25

= -75 %

hence area of circle will be decreased by 75% .
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