**Question:**

Wasim bought two cricket bats for ₹ 840 and ₹ 360 respectively. He sells the first bat at a gain of 15% and the second one at a loss of 5%. Find his gain or loss per cent in the whole transaction.

**Solution:**

CP of the first bat = ₹840

Profit% on the first bat = 15%

$\therefore$ Profit $=15 \%$ of ₹ $840=\frac{15}{100} \times 840=₹ 126$

SP of the first bat = ₹840 + ₹126 = ₹966

CP of the second bat = ₹360

Loss $=5 \%$ of ₹ $360=\frac{5}{100} \times 360=₹ 18$

SP of the second bat = ₹360 − ₹18 = ₹342

Total CP of two bats = CP of first bat + CP of second bat = ₹840 + ₹360 = ₹1,200

Total SP of two bats = SP of first bat + SP of second bat = ₹966 + ₹342 = ₹1,308

Here, Total SP of two bats > Total CP of two bats.

Gain = Total SP of two bats − Total CP of two bats = ₹1,308 − ₹1,200 = ₹108

$\therefore$ Gain $\%$ in the whole transaction $=\frac{\text { Gain }}{\text { Total CP of two bats }} \times 100 \%=\frac{108}{1200} \times 100=9 \%$