1.  ₹ 9800 are invested partly in 9% stock at 75 and 10% stock at 80 to have equal amount of incomes. The investment in 9% stock is:
A. ₹ 4800
B. ₹ 5000
C. ₹ 5400
D. ₹ 5600

Answer: Option B

Explanation:

Let the investment in 9% stock be ₹ x.

Then, investment in 10% stock = ₹ (9800 - x).

9 x x = 10 x (9800 - x)
75 80

3x = 9800 - x
25 8

24x = 9800 x 25 - 25x

49x = 9800 x 25

x = 5000.