The simple interest on a certain sum for 3 years at 8% per annum is ₹ 9120 less than the simple interest on the same sum for 7 years at 8% per annum. Find the sum.
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e ₹ 28500.
Given that
S.I. at 8% per annum for 7 years - S.I. at 8% per annum for 3 years = 9120
Let a certain amount of sum be P
Formula used
S.I. = PRT/100
where, P is the sum, R = rate of interest, T = time
Calculation
⇒ P × 8 × 7/100 - P × 8 × 3/100 = 9120
⇒ 32P = 912000
⇒ P = 912000/32
⇒ P = ₹28500