Question

A mixture contains milk and water in the ratio of $4:3$ respectively. If $6$ L of water is added to this mixture the respective ratio of milk and water becomes $8:7$. What is the quantity of milk in the original mixture?

• A. $48$ litres
• B. $47$ litres
• C. $46$ litres
• D. $45$ litres

Answer 1

Answer: (A)

$48$ litres

$M:W=4:3$...................................(1)

When $6L$ is added to the mixture

$\Rightarrow \frac{M}{W+6}=\frac{8}{7}$

$\Rightarrow 7M=8W+48$....................................(2)

From Eq(1)

$M=\frac{4W}{3}$

putting value of $M$ in (2)

$\Rightarrow 7\frac{4W}{3}=8W+48$

$\Rightarrow W=36$

Using

$\Rightarrow$ $M=\frac{4W}{3}$

$\Rightarrow M=48$

Therefore Answer is $\left(A\right)$