Question

A sum of money double itself in 8 years at a certain rate . In how many years will it become triple of itself at the rate at the rate of simple interest​

Answer 1

Answer:

The rate of interest is 12.5%

The sum will become triple of itself in 16 years.

Step-by-step explanation:

The simple interest is calculated using principal, time and rate of interest.

Part I

Let us consider the sum of money as P and the amount as given in the question is 2P at the end of 8 years.

S.I=amount-principal=2P-P=P

Let us assume the rate of interest is R%.

$S.I=\frac{PTR}{100}\\P=\frac{8PR}{100} \\R=\frac{100}{8} =12.5$

The rate of interest is 12.5%

Part II

The amount as given in the question is 3P.

S.I=amount-principal=3P-P=2P

Let us assume the time as T years.

$S.I=\frac{PTR}{100}\\2P=\frac{25PT}{2.100} \\2=\frac{T}{2.4} \\T=2.2.4=16$

The time in which the sum become triple of itself at 12.5% is 16 years.