Question

The C.P of 15 books is equal to the S.P of 18 books.
Find his gain% or loss%

Answer 1

Solutions :-


Given :

Cost Price of 15 books is equal to the cost price of 18 books.

Find the LCM of 15 and 18 :-

LCM of 15 and 18 is 90


Therefore,
Cost Price of 15 books = Rs 90
Cost Price of 1 book = Rs (90/15) = Rs 6

Selling price of 18 books = Rs 90
Selling price of 1 book = Rs (90/18) = Rs 5


Now,
We have,

Cost Price of 1 book = Rs 6
Selling price of 1 book = Rs 5


Cost Price is greater than the Selling price. Therefore, Loss.

Loss = C.P - S.P
= Rs (6 - 5)
= Rs 1


Loss % = (Loss × 100)/C.P %
= (1 × 100)/6 %
= 100/6 %
= 16.66 % approx.


Hence,
Loss percent = 16.66% or 16⅔%

Answer 2

Solutions :-

We have,

Cost Price of books = 18
Selling price of books = 15

Cost Price > Selling price

Find the Loss percent :-

$Loss = ( \frac{cp - sp}{cp} \times 100)\% \\ \\ = ( \frac{18 - 15}{18} \times 100)\% \\ \\ = ( \frac{3}{18} \times 100)\% \\ \\ =( \frac{50}{3} )\% \: = 16 \frac{2}{3} \%$

Answer : Loss percent = 16⅔ %