Hasan sold an article for 56 taka which cost him x taka. If he had gained x% on his outlay, what was his cost?

A 40 taka

B 45 taka

C 36 taka

D 28 taka

Correct Answer: Option A

Hasan sold an article for 56 taka which cost him x taka

So, Profit = (56-x)

Again he had gained x% on his outlay,

So Profit = x*x/100

We get,

x2/100 = 56 - x

x2/100 +x- 56 =

x2 +100x -5600 = 0

x2 + 140x -40x -5600 = 0

x(x + 140) - 40 (x + 140) =0

(x-40) (x+140)=0

x=40