Question

A length of a side of a square is increased by 10% then the area what percent increased

Answer 1

Let the side of square be x

Area will be x²

Now as the side is increased by 10% the length of new side is

(10/100)*x + x. As the initial side was x and a 10% increase so the new side wld be 10% of old + old

That is (x/10) + x that is (11/10)x

So the new area is (121/100) x² or 121%Also as the old area was (100/100) x² or 100%

Therefore the increase in area is 121–100= 21

If u cant solve such ques by algebra u can put the side as 10cm as an example and try solving the ques. Make sure u put the side length as a multiple of 10 so that it wld be easy for calculations purpose.

As the side is 10 and 10% of 10 is 1 the new side is 10+1=11 the old area was 10² which is 100 while the new area is 11² which is 121. The percentage increase is given by (new area percent-old area percent) %

(121/100–100/100)% which is 21%!!