Question

The price price of an article is reduced by 10%. By how much per cent this value be increased to restore it to its former value ?

Answer 1

Let a number be 100
Its decreased by 10%= 100- (10/100×100)
= 90

Let the increase % be x

90+(x/100×90)= 100
90+ 90x/100
90x/100= 100-90
x= 10×100/90
x= 100/9 % or 11 whole 1 by 9 %

that is 11 1/9 %