Question

Some toffees are bought at the rate of 11 for Rs. 10 and the same number at the rate of 9 for Rs. 10. If the whole lot is sold at one rupee per toffee, find the gain or loss percent on the whole transaction.

Answer 1

LCM of 11 and 9 = 99
Let each time 99 toffees are bought
In first case, the C.P of 99 toffees at the rate of 11 for Rs. 10
$=\frac{99\times 10}{11}=Rs.90$
In second case, the C.P of 99 toffees
at the rate of 9 for Rs. 10 $=\frac{99\times 10}{9}$
=Rs. 110
$\therefore$ Total cost price of 99 + 99 = 198 toffees
=Rs. 90 + Rs. 110 = Rs. 200
and S.P of 198 toffees at the rate of one rupee each = Rs. 198 \times 1 = Rs. 198
$\therefore$ Loss = C.P - S.P = Rs. 200 - 198 = Rs. 2
$\therefore Loss\%=\frac{Loss\times 100}{C.P}=\frac{2\times 100}{200}=1\%$