If 10 apples are bought for ₹ 11 and sold at the rate of 11 apples for ₹ 10. Find the overall gain or loss per cent in these transactions.
CP of 10 apples = ₹ 11
CP of 1 apple = ₹ 11/10
SP of 11 apples = ₹ 10
SP of 1 apple = ₹ 10/11
Clearly CP > SP (∵ 11/10 > 10/11)
∴ Loss = Rs (11/10 – 10/11)
= Rs (121-100)/110 = Rs 21/110
On Rs 11/10, the loss = Rs 21/110
On Rs 1, the loss = Rs 21/110 × 10/11
On Rs 100, the loss = Rs 21/110 × 10/11 × 100
= 2100/121 % = 17 43/121%
Hence, the overall loss = 17 43/121%.