NCERT Exemplar Solutions
Class 7 - Mathematics - Unit 7: Comparing Quantities - Problems and Solutions
Question 135

Question. 135

The simple interest on a certain sum for 2.5 years at 12% per annum is ₹ 300 less than the simple interest on the same sum for 4.5 years at 8% per annum. Find the sum.

Answer:

Sum = ₹ 5,000

Detailed Answer with Explanation:

SI₁ = (P × 12 × 2.5)/100 = 0.3P.
SI₂ = (P × 8 × 4.5)/100 = 0.36P.
Difference = 0.36P − 0.3P = 0.06P = 300.
P = 300 / 0.06 = ₹ 5,000.

NCERT Exemplar Solutions Class 7 – Mathematics – Unit 7: Comparing Quantities – Problems and Solutions | Detailed Answers