Question

A sum was put at simple interest at a certain rate for $4$ years. Had it been put at $2$% higher rate, it would have fetched Rs $56$ more. Find the sum.

• A. Rs $680$
• B. Rs $690$
• C. Rs $700$
• D. Rs $720$

Answer 1

The correct option is C Rs $700$

$\Rightarrow$ Let sum be $P$ and original rate be $R$. Then

$\Rightarrow$ $\frac{P\times (R+2)\times 4}{100}-\frac{P\times R\times 4}{100}=56$

$\Rightarrow$ $4P\times (R+2)-4P\times R=5600$

$\Rightarrow$ $4PR+8P-4PR=5600$

$\Rightarrow$ $8P=5600$

$\therefore$ $P=Rs.700.$