The difference between the compound and simple interest on a certain sum for 2…
2024
The difference between the compound and simple interest on a certain sum for 2 years at the rate of 10% per annum is Rs 90 . What is the sum ?
- A.
7500
- B.
8000
- C.
9000
- D.
10000
Attempted by 14 students.
Show answer & explanation
Correct answer: C
Key idea: The difference between compound interest and simple interest for 2 years equals principal × (rate/100)².
Let the principal be P.
Use the formula: difference = P × (r/100)².
Substitute r = 10: difference = P × (10/100)² = P × 0.01 = P/100.
Set this equal to the given difference 90: P/100 = 90 ⇒ P = 90 × 100 = 9000.
Therefore the required sum is 9000.