Question

A sum of money becomes 6 times in 20 years at S.I. find the rate of interest.

Answer 1

6 times in 20 years means 5 times is interest and 1 time principal.

interest is equal to principal in 4 (= 20/5) years. Being Simple Interest = 100/4 = 25%

Answer 2

Answer:

25%

Step-by-step explanation:

Let Principal be P

Amount = 6P

Interest = Amount - Principal = 6P - P = 5P

Time = 20 years

Let R be the rate of interest

Formula :$SI = \frac{P\times R \times T}{100}$

$5P = \frac{P\times R \times 20}{100}$

$5 = \frac{R \times 20}{100}$

$\frac{500}{20} = R$

$25\% = R$

Hence the rate of interest is 25%