The simple interest on Rs. 10 for 4 months at the rate of 3 paise per rupee…

2025

The simple interest on Rs. 10 for 4 months at the rate of 3 paise per rupee per month is

  1. A.

    1.00

  2. B.

    1.20

  3. C.

    1.22

  4. D.

    1.98

Show answer & explanation

Correct answer: B

Simple interest is found using SI = (P × R × T) / 100, where P is the principal, R is the rate percent per period, and T is the number of periods. When a rate is given in paise per rupee per period, convert it to a percentage first: since 1 rupee = 100 paise, a rate of r paise per rupee per month is the same as r% per month.

  1. Principal P = Rs. 10; rate = 3 paise per rupee per month = 3% per month; time T = 4 months.

  2. Apply the formula: SI = (P × R × T) / 100 = (10 × 3 × 4) / 100.

  3. Compute the product first: 10 × 3 × 4 = 120, so SI = 120 / 100 = Rs. 1.20.

Cross-check with the direct paise method: each rupee earns 3 paise of interest per month, so Rs. 10 earns 10 × 3 = 30 paise per month; over 4 months this is 30 × 4 = 120 paise, i.e. Rs. 1.20, matching the result above.

Explore the full course: Amcat Preparation