Question

A grocer bought sugar worth $Rs.4500$ . He sold one-third of it at again of $10\%$ . At what gain per cent must the remaining sugar be sold to have a gain of $12\%$ on the whole?

Answer 1

$\text{C.P. of sugar = Rs. 4500}\text{C.P. of}\frac{1}{3}ofsugar=Rs.4500\times \frac{1}{3}=Rs.1500Gain\%=10\%\therefore S.P.=\frac{C.P.(100+gain\%)}{100}=Rs.\frac{1500\times (100+10)}{100}=Rs.1500\times \frac{110}{100}=Rs.1650Gainontotal=12\%\therefore TotalS.P.=\frac{C.P.(100+gain\%)}{100}=Rs.\frac{4500(100+12)}{100}=Rs.\frac{4500\times 112}{100}=Rs,5040RemainingC.P=Rs.4500-Rs.1500=Rs.3000andramainingS.P.=Rs.5040-Rs.1650=Rs.3390\therefore Gain=S.P.-C.P=Rs.3390-Rs.3000=Rs.390Gain\%=\frac{gain\times 100}{C.P}=\frac{390\times 100}{3000}=13\%Ans.$