The amount of a certain sum invested for 3 1/2 years at simple interest is…
2022
The amount of a certain sum invested for 3 1/2 years at simple interest is Rs.6648 at a certain rate per cent per annum. The amount of the same sum invested for 6 years at simple interest is Rs.7,968 at the same rate. The sum (in Rs.) is:
- A.
4500
- B.
4800
- C.
5000
- D.
5200
Attempted by 25 students.
Show answer & explanation
Correct answer: B
Amount in 6 years = Rs. 7968
Amount in 3.5 years = Rs. 6648
Step 1: Find the interest for the difference in time.
Time difference = 6 - 3.5 = 2.5 years.
Simple Interest for 2.5 years = 7968 - 6648 = 1320.
Step 2: Find the interest for 1 year.
Interest for 1 year = 1320 / 2.5 = 528.
Step 3: Find the interest for 3.5 years.
Interest for 3.5 years = 528 * 3.5 = 1848.
Step 4: Calculate the Principal (Sum).
Sum = Amount (after 3.5 years) - Interest (for 3.5 years)
Sum = 6648 - 1848 = 4800.
Final Answer: Option B