Question -
Answer -
Using matrix multiplication, determine how to divide Rs 30,000 among the two types of bonds. If the trust fund must obtain an annual total interest of:
(a) Rs 1,800 (b) Rs 2,000
Solution
(a) Let Rs x be invested inthe first bond. Then, the sum of money invested in the second bond will be Rs
(30000 − x).
It is given that thefirst bond pays 5% interest per year and the second bond pays 7% interest peryear.
Therefore, in order toobtain an annual total interest of Rs 1800, we have:
Thus, in order toobtain an annual total interest of Rs 1800, the trust fund should invest Rs15000 in the first bond and the remaining Rs 15000 in the second bond.
(b) Let Rs x be invested inthe first bond. Then, the sum of money invested in the second bond will be Rs
(30000 − x).
Therefore, in order toobtain an annual total interest of Rs 2000, we have:
Thus, in order toobtain an annual total interest of Rs 2000, the trust fund should invest Rs5000 in the first bond and the remaining Rs 25000 in the second bond.