A manufacturer has 600 L of a 12% solution of acid. How many litres of a 30% acid solution must be added to it so that the acid content in the resulting mixture will be more than 15% but less than 18%?
Let x litres of 30% acid solution is required to be added. Then
Total mixture = (x + 600) litres
Therefore
30% x + 12% of 600 > 15% of (x + 600)
and 30% x + 12% of 600 < 18% of (x + 600)
Total mixture = (x + 600) litres
Therefore
30% x + 12% of 600 > 15% of (x + 600)
and 30% x + 12% of 600 < 18% of (x + 600)