Question

Simple interest on a certain sum at a certain annual rate of interest is $\frac{1}{9}$. If the numbers representing rate percent and time in years be equal, then rate of interest is :

• A. $3\frac{1}{3}\%$
• B. $5\%$
• C. $6\frac{2}{3}\%$
• D. $10\%$

Answer 1

The correct option is A $3\frac{1}{3}\%$

$SI=\frac{1}{9}P,R=T$

$SI=\frac{P\times R\times T}{100}$

$\Rightarrow \frac{1}{9}P=\frac{P\times R\times T}{100}$

$=R^2=\frac{100}{9}$

$\Rightarrow R=\frac{10}{3}=3\frac{1}{3}\%$