Divide ₹ 35,400 into two parts such that if one part is invested in 9%, ₹ 100 shares at 4% discount, and the other in 12%, ₹ 50 shares at 8% premium, the annual incomes are equal.

Divide ₹ 50,760 into two parts such that if one part is invested in 8%, ₹ 100 shares at 8% discount and the other in 9%, ₹ 100 shares at 8% premium, the annual incomes from both the investments are equal.

Which is the better investment:

(12%, ₹ 20 shares at ₹ 16) or (15%, ₹ 20 shares at ₹ 24)?

Ashish bought 4,500, ₹ 10 shares paying 12% per annum. He sold them when the price rose to ₹ 23 and invested proceeds in ₹ 25 shares paying 10% per annum at ₹ 18. Find the change in his annual income.