Question

. A grocer bought sugar worth Rs4500. He sold one-third of it at a gain of 10%. At what gain per cent must the remaining sugar be sold to have a gain of 12% on the whole?

Answer 1

Assume that the grocer bought 3 kg sugar
C.P of 3 kg = 4500
C.P per kg = 1500

one-third was sold at a gain of 10%
C.P of 1 kg = 1500
Gain = 10%
S.P = C.P*(100+G)/100 = 1500*110/100 = Rs.1650

Overall gain to be obtained = 12%
Total C.P = 4500
Total S.P = 4500*112/100 = 5040

S.P of remaining 2 kg = 5040 - 1650 = 3390
C.P of 2 kg = 3000
Gain = 390
Gain% = G/C.P * 100 = 390/3000 * 100 = 13%
Hence the remaining sugar should be sold at 13% gain.
Hope it helps