How much water must be added to a 30 quarts of a 75% acid solution to reduce it to a 15%
solution of acid?	Choose the most appropriate option:  A) 120 qts  B) 220 qts  C) 320 qts  D) 420 qts  E) 520 qts
I’m adding water, so we have   WATER + WATER = WATER   Starting off with 30 quarts and adding x quarts, we should end up with (30 + x) quarts   30 + x = (30 + x)   The problem describes the solution in terms of acid, we have set it up in terms of water. So, we   have to change the percentages and put them in the problem.   .25(30) + x = .85(30 + x)   Again, we multiply both sides of the equation by 100 to get rid of the decimal point.   25(30) + 100x = 85(30 + x)   750 + 100x = 2550 + 85x   15x = 1800   x = 120 qts   correct answer 120 qts
<result>A</result>
How much water must be added to a 30 quarts of a 75% acid solution to reduce it to a 15%
solution of acid?