Question

If a certain sum of money amounts to <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> $\frac{7}{4}$th of itself in three years, the rate percent per annum is:

• A. 20%
• B. 25%
• C. 28%
• D. 32%

Answer 1

The correct option is B 25%

Let the principal be $p$.

So, Amount = <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> $\frac{7}{4}$p

Therefore,
$SI$ = Amount - Principal = $\frac{7}{4}$$p$ - $p$ = $\frac{3}{4}p$

Given, Time = 3 years

By formula
$R$ = <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> $\frac{SI\times 100}{Time\times Principal}$

$R$ = $\frac{\frac{3}{4}p\times 100}{3\times P}$ = $\frac{100}{4}$% = $25$%