Mrs. Kulkarni invests ₹ 1,31,040 in buying ₹ 100 shares at a discount of 9%. She sells shares worth ₹ 72,000 at a premium of 10% and the rest at a discount of 5%. Find her total gain or loss on the whole.

Investment = ₹ 1,31,040

N.V. of 1 share = ₹ 100

Discount = 9% of ₹ 100 = ₹ 9

∴ M.V. of 1 share = ₹ 100 - ₹ 9 = ₹ 91

∴ No. of shares purchased = $\dfrac{\text{Investment}}{\text{M.V. of 1 share}} = \dfrac{131040}{91}$ = 1440

No. of shares worth ₹ 72,000 = $\dfrac{72000}{100} = 720$

∴ Mrs. Kulkarni sells 720 shares at a premium of 10%

M.V. of 1 share = ₹ 100 + ₹ 10 = ₹ 110

∴ Selling price of 720 shares = 720 × ₹ 110 = ₹ 79,200

No. of remaining shares = 1440 - 720 = 720.

She sells 720 shares at a discount of 5%

M.V. of 1 share = ₹ 100 - ₹ 5 = ₹ 95

∴ Selling price of 720 shares = 720 × ₹ 95 = ₹ 68,400

∴ Total selling price = ₹ 79,200 + ₹ 68,400 = ₹ 1,47,600

∴ Total gain = Total selling price - Total investment = ₹ 1,47,600 - ₹ 1,31,040 = ₹ 16,560.

Hence, total gain = ₹ 16,560.