Answer: There are 16 cups in every gallon so we could divide 152 by 16 and get our number of gallons which would give us 9.63 or a little over 9 and a half gallons.
Step-by-step explanation:
If you set up a proportion, this will make sense.

Now, Cross Multiply
6x = 12.5
x = 25/12
B - 3A = 2
3B - 6A = 12
(2)B - (6)A =4
3B - 6A = 12
Subtract
-B = -8
B = 8
Plugin 8 for B
8 - 3A = 2
8 = 3A + 2
6 = 3A
2 = A
(Double checking)
3(8) - 6A = 12
-6A = 12-24 = -12
- 6A = -12
Divide by -6
A= 2
It works
A = 2. B = 8. Hope this helps