A man lends out a sum of money by putting 40% of it at 7.5% p.a. simple interest and the remaining 60% at 11.25% p.a. simple interest.After 2½ years (2.5 years) his total interest income is ₹6,825. What was the original sum (principal) he lent?
Show answer & explanation
Correct answer: B
Explanation
Given:
Total amount = x
40% amount → 7.5% per annum simple interest
60% amount → 11.25% per annum simple interest
Time = 2.5 years
Total interest = Rs.6825
According to the sources:
Simple interest = PRT /
Interest of the first part= (0.40x × 7.5 × 2.5) / 100= 0.075x
Interest of the second part= (0.60x × 11.25 × 2.5) / 100= 0.16875x
Total Interest
0.075x + 0.16875x = 6825
0.24375x = 6825
x = 6825/0.24375
x = 28000
Total amount = Rs 28000