Question

Find the annual rate of interest. Principal = 4600 rupees, Period = 5 years, Total amount = 6440 rupees, Annual rate of interest = __%

Answer 1

The annual rate of interest per year is 8%

Solution:

Given:- Principal (p) = 4600 rupees, Time –Period (t) = 5 years, Total amount(A) = 6440 rupees

First we will calculate the Interest and then using formula of simple interest we will calculate the rate of interest

Interest = Amount – Principal

Interest = 6440  – 4600 = 1840

Now using the formula of simple Interest and on putting values we get,

$\text {Simple Interest }=\frac{P \times R \times T}{100}$

Where "P" is the principal and "R" is the rate of interest per annum and "T" is the time period

$1840=\frac{4600 \times R \times 5}{100}$

$\begin{aligned} \mathrm{R} &=\frac{1840 \times 100}{4600 \times 5} \\\\ \mathrm{R} &=\frac{1840}{230} \\\\ \mathrm{R} &=8 \% \end{aligned}$

Hence, the required rate of interest per year is 8%