Discussion Forum

Shyam lent Rs. 600 for 2 years and Rs. 200 for 3 years, at the same rate at simple interest, and received Rs. 90 as total interest. What was the rate % p.a. ?

Answer:

Explanation:

Total $SI$ $=\frac{P_{1}T_{1}R}{100}$ $+\frac{P_{2}T_{2}R}{100}$

$R$ = rate % which is the same in both cases.

$\Rightarrow\frac{600\times 2\times R}{100}$ $+\frac{200\times 3\times R}{100}$ $=90$

$12R+6R$ $=90$ $\Rightarrow 18R=90$ $\Rightarrow R$ = 5%