# A 70% salt solution was diluted with purified water to produce about 50 liters of 55% salt solution. Approximately how much purified water was used?

Feb 24, 2018

see a solution process below;

#### Explanation:

Let the amount of purified water used be $x$

Now interpreting the statement;

70%(50 - x) = 55%(50)

$\frac{70}{100} \left(50 - x\right) = \frac{55}{100} \left(50\right)$

$0.70 \left(50 - x\right) = 0.55 \left(50\right)$

$35 - 0.70 x = 27.5$

Collecting like terms..

$35 - 27.5 = 0.70 x$

$7.5 = 0.70 x$

Divide both sides by $0.70$

$\frac{7.5}{0.70} = \frac{0.70 x}{0.70}$

$x = \frac{7.5}{0.70}$

$x = 10.7$

$x \approx 11 L$

Hence the purified water was used is approximately $11 L$