Question

In how many years rupees 600 are amount to rupees 726 at a compound interest of 10 p.c.p.a. *

Answer 1

Solution!!

The concept of compound interest has to be used here. The amount, principal and rate of interest is given in the question. According to the question, we have to find the time.

Amount = Rs 726

Principal = Rs 600

Rate of interest = 10%

Time = x

Let's use a suitable formula and find the number of years.

Amount = P(1 + (R/100))ⁿ

726 = 600(1 + (10/100))ˣ

Divide both sides of the equation by 6.

121 = 100(1 + (10/100))ˣ

Calculate the sum.

121 = 100(11/10)ˣ

Swap the sides of the equation.

100(11/10)ˣ = 121

Divide both the sides of the equation by 100.

(11/10)ˣ = 121/100

Write the number in exponential form with the base 11/10.

(11/10)ˣ = (11/10)²

Since the bases are same, set the exponents equal.

x = 2

Hence,

Time = 2 years

Abbreviations used:-

P → Principal

R → Rate of interest

n → Time