Question

A mixture contains forty ounces of glycol and water and is ten percent glycol. If the mixture is to be strengthened to twenty-five percent, how much glycol is to be added?
1. 4 oz
2. 8 oz
3. 10 oz

Answer 1

2. 8 oz...................

Answer 2

40oz glycol and water
10% is glycol
4oz is glycol
36oz is water

if glycol is to be added to make glycol 25% of all then
note: water does not change
100-25=75
water does not change so
36oz=75%
12=25%

there should be 12 oz of glycol total
4 now
12-4=8
8 oz should be added


sorry, I just wrote what I was thinking


answer is 8oz