A principal lends on simple interest for two years. If rate of interest more than 1% the simple interest increased by Rs. 240. Find out the principal:
1. Rs. 5,000
2. Rs. 6,000
3. Rs. 8,000
4. Rs. 12,000
1. Rs. 5,000
2. Rs. 6,000
3. Rs. 8,000
4. Rs. 12,000
Correct Answer – Option 4 : Rs. 12,000
Given:
Simple interest more than 1% the simple interest increased = Rs. 240
Time = 2 years
Concept used:
S.I. = (P × R × T)/100
Calculation:
S.I. = (P × R × 2)/100 —-(1)
S.I. = [P × (R + 1) × 2]/100 —-(2)
Equation (1) subtract from equation (2)
[P × (R + 1) × 2]/100 – (P × R × 2)/100 = 240
⇒ P[(R + 1) × 2 – (R × 2)]/100 = 240
⇒ P(2R + 2 – 2R) = 240 × 100
⇒ P × 2 = 24000
⇒ P = 24000/2
⇒ P = 12000
∴ The principal lends on simple interest for two years is Rs. 12000.