Question

If the simple interest earned on a certain sum for 3 years at the rate of 12.5% is Rs. 1250 less than the sum investment then find the C.I on the same sum for 2 years at the rate of 10% per annum?
1. Rs. 420
2. Rs. 220
3. Rs. 210
4. Rs. 250
5. None of these

Answer 1

Correct Answer - Option 1 : Rs. 420

GIVEN:

⇒ Rate = 12.5%

⇒ Time = 3 year

⇒ Simple interest = Compound interest – 1250

FORMULA USED:

1) Effective rate = a + b + a x b/100

CONCEPT USED:

1) Unitary method.

2) Principle = 100%

CALCULATION:

 S.I = 12.5% x 3 = 37.5%

 Difference = 62.5%

 62.5% = Rs. 1250

⇒ 1% = Rs. 20

 P = 100% = Rs. 2000

Now Compound interest,

P = Rs. 2000

R = 10%             

T = 2 years.

⇒ Effective rate = 21%

⇒ C.I = 21% of 2000

⇒ C.I = Rs. 420

Therefore the correct answer is Rs.420