The compound interest on Rs. 30,000 at 7% per annum for

Home » Aptitude » Compound Interest » Question

The compound interest on Rs. 30,000 at 7% per annum for n years is Rs. 4347. The value of n is

1. 3
2. 2
3. 4
4. 5

Correct Option: B

Here , Principal = Rs. 30000 , CI = Rs. 4347 , Rate = 7% , Time = n years
Amount = Principal + CI = Rs. (30000 + 4347) = Rs. 34347
Using the given formula ,

A = P		1 +	R		^T
			100

⇒ 34347 = 30000		1 +	7		ⁿ
			100

⇒	34347	=		107		ⁿ
	30000			100

⇒	11449	=		107		ⁿ
	10000			100

⇒		107		²	=		107		ⁿ
		100					100

On equating powers both sides ,
⇒ n = 2 years