Question

$A$ and $B$ have a monthly incomes in the ratio $5:6$ and monthly expenditures in the ratio $3:4$. If they save $Rs.1800$ and $Rs.1600$ respectively, find the monthly income of $B$.

• A. $Rs.3400$
• B. $Rs.2700$
• C. $Rs.1720$
• D. $Rs.7200$

Answer 1

The correct option is D $Rs.7200$

Let the monthly incomes of $A$ and $B$ be $Rs.5x$ and $Rs.6x$ respectively.
Then, $\frac{5x-1800}{6x-1600}=\frac{3}{4}$
$\Rightarrow 20x-7200=18x-4800$
$\Rightarrow 2x=2400\Rightarrow x=1200$
$\therefore$ Monthly income of B$=6\times Rs.1200=Rs.7200$.