Question

An auto technician has 12 ounces of battery acid that is 75% acid. How many ounces of water must the technician add to make a solution that is 25% acid?

Answer 1

75 % of 12 = 9 ounce

Answer 2

and 3 ounce of water

Answer 3

new total = 12+x
water = 3+x
acid = 9

Answer 4

\[\frac{ 9 }{ 12+x }=\frac{ 25 }{ 100 }\]

Answer 5

\[\frac{ 9 }{ 12+x }=\frac{ 1 }{ 4 }\]

Answer 6

9*4=12+x
36=12+x
x=24