Question

A person deposited $Rs.400$ for $2$ years, $Rs.550$ for $4$ years and $Rs.1200$ for $6$ years at the same rate of simple interest. If he received a total interest of $Rs.1020$, what is the rate of interest per annum?

• A. $5\%$
• B. $10\%$
• C. $15\%$
• D. $20\%$

Answer 1

Answer: (B)

$10\%$

Let $R$ be the rate of interest per annum, then,

$\frac{400\times 2\times R}{100}+\frac{550\times 4\times R}{100}+\frac{1200\times 6\times R}{100}=1020$

$\Rightarrow 8R+22R+72R=1020$

$\Rightarrow 102R=1020$

$\Rightarrow R=\frac{1020}{102}$

$\Rightarrow R=10\%$