A certain amount is invested at a certain simple interest rate for a period of 6 years If the amount...........

Quantitative Aptitiude (CLAT) Simple Interest

A certain amount is invested at a certain simple interest rate for a period of 6 years. If the amount is invested at 3% more rate then it has fetched Rs 900 more. Find the Principle amount.

Rs 3500

Rs 4000

Rs 4500

Rs 5000

Explanation:

Let the simple interest be Rs x
The Simple Interest formula
X = PTR / 100
Where P is Principle, T = time period, R = Rate of interest. T = 6 years, let Rate of interest be R; then
X = 6PR / 100 ----------- (1)
If the rate of interest was 3% more, then Simple Interest would be Rs 900 more, X + 900 = [P* 6 * (R + 3) ] / 100
900 + x = (6PR + 18 P) / 100
900 + x = (6PR / 100) + 18P / 100
From (1) we know that 6PR / 100 = x
Substituting the value in the above equation we get
900 + x = x + (18P / 100) 900 = 18P / 100
P = Rs 5000/-