Question

At what rate of interest a sum of money doubles itself in 10 years in simple interent?​

Answer 1

Answer:

Step-by-step explanation:

A simple tool is the rule of 72. 72/interest rate = time to double. So 72/10 years = about 7.2% annual interest doubles in 10 years.

Answer 2

Answer:

$\boxed{R = 10 \text{ percent}}$

Step-by-step explanation:

$\text{Let the investment be Rs. 100}\\\\\\\boxed{I = \frac{PRT}{100}}\\\\\\\boxed{A = P + I}\\\\\\\text{Therefore, } 200 = 100 + I\\\\\text{Therefore, we need to find the rate at which the interest would become} \text{ Rs. 100 in 10 years}\\\\100 = \frac{100 \text{ x } R \text{ x } 10}{100}\\\\10R = 100\\\\\boxed{R = 10 \text{ percent}}$

Hope this helps!