Question

The simple interest earned on a certain amount is double the amount when invested for 10 years. what is the interest rate being offered?

Answer 1

Let amount be x. Given time= 10 yrs

Given simple interest be doubled, so S.I = 2x

From the formula S.I = PTR / 100

2x = x*10*R / 100

2=R/10

R=20%

Answer 2

Rate of Interest being offered is 20 %.

Explanation:

When invested amount is getting double after 10 years then rate of interest would be 20%.  

Let us say for example

X is investing 100 rs for 10 years at the rate of 20 %.  

Then, solution would be as below.

A =$\frac{PNR}{100}$

A = $100 \times 10 \times 0.20$

A = Rs. 200  

If X is investing Rs. 200 rs for 10 years at the rate of 20 % then A would be Rs. 400.