Question

$85$ L of a mixture contains milk and water in the ratio $27:7$ How much more water is to be added to get a new mixture containing milk and water in the ratio $3:1$?

• A. 5$L$
• B. 6.5$L$
• C. 7.25$L$
• D. 8$L$

Answer 1

Answer: (A)

5$L$

$Milk:Water=27:7$

$Milk=27x$

$Water=7x$

$27x+7x=34x=85l$

$x=\frac{85}{34}$

$Milk=27x=\frac{27\times 85}{34}=67.5l$

$Water=7x=\frac{7\times 85}{34}=17.5l$

New ratio$=3:1$

Let k l of water be added to the mixture.

$\frac{3}{1}=\frac{67.5}{17.5+k}$

$52.5+3k=67.5$

$3k=67.5-52.5$
$3k=15$

$k=5l$