Question

The Banker's discount on a sum of money for $18$ months is Rs$600$ and the true discount on the same sum for $3$ years is Rs$750$/-. The percentage is:

• A. $10\%$
• B. $20\%$
• C. $15\%$
• D. $12\%$

Answer 1

Answer: (B)

$20\%$

Here,
BD = Banker's discount and TD = True discount.
$\therefore$ According to question;
BD for $\left(\frac{3}{2}\right)years=600$
$\therefore$ BD for $3$ years = $1200$
Now, BD = $1200$, TD = $750$ and Time = $3$ years
$\therefore$ Sum $=\frac{\text{B.D X T.D}}{\text{B.D - T.D}}=\left[\frac{1200\times 750}{450}\right]=2000$
$\therefore$ Rs$1200$ is S.I on Rs $2000$ for $3$ years
So, rate = $\left[\frac{100\times 1200}{200\times 3}\right]\%=20\%$