Question

a book seller losses 13 p.c by selling a book at a certain price .if he had sold it for 9.75 more ,he would have gained 26 percentage find the cost price of the book .

Answer 1

Loss % = 13%

Let the Cost Price (CP) be Rs. x

SP = CP - CP * (P%/100)

SP = x - x * (13/100)

SP = (100x - 13x)/100

SP = Rs. 87x/100

Condition : if he had sold it for 9.75 more ,he would have gained 26%

So,

New SP = Rs. (87x/100) + 9.75 = (87x+975)/100

Gain % = 26%

CP = (SP * 100)/ (100 + G%)

x = (((87x+975)/100 )*100) / 126

126x = 87x+975

126x - 87x = 975

39x = 975

x = 975/39

x = 25

CP = Rs. 25