Question

A commodity is sold at $20$% discount, still $10$% is gained by selling it. Calculate the cost price of the article whose selling price is Rs. $220.$

Answer 1

S.P. M.P. C.P.

80 100 $(\frac{100}{110}\times 80)$

S.P. : C.P. :: S.P. : C.P.

$80:(\frac{100}{110}\times 80)=220:x$

[Using method of proportion]

$\therefore x=\frac{100}{110}\times 80\times \frac{220}{80}$

$=Rs.200$