Question

By selling cloth at $Rs.9$ per metre, the shopkeeper loses $10\%.$ Find the twice of selling price in $Rs.$ per metre when the gain $15\%?$

Answer 1

For the first situation,
Loss % $=\frac{C.P.-S.P.}{C.P.}\times 100=10$
$=>C.P.-9=0.1C.P.$
$=>0.9C.P.=9$
$C.P.=Rs10$
So, for Profit % $=\frac{S.P.-C.P.}{C.P.}\times 100=15$
$=>\frac{S.P.-10.}{10}\times 100=15$
$=>S.P.-10=1.5$
$=>S.P.=Rs11.50$ per meter

twice of selling price would be $11.50\times 2=23$