Question

90% and 97% pure acid solutions are mixed to obtain 21 litres of 95% pure acid solution. Find the quantity of each type of acids to be mixed to from the mixture.

Answer 1

Correct Answer - 6 litres, 15 litres
Let x litres of 90% pure solution be mixed with y litres of 97% pure solution to get 21 litres of 95% pure solution.
Then, ` x + y = 21 " " `… (i)
and ` (90x)/(100) + (97y)/(100) = ( 95 xx 21)/(100)rArr 90x + 97 y = 1995" "`... (ii)
Now, solve (i) and (ii).