Answer:
24
Step-by-step explanation:
Let t represent the volume of the tank in gallons. Then we have ...
(1/8)t + 15 = (3/4)t . . . . . . . . . . . adding 15 gallons fills the tank to 3/4
15 = (6/8 -1/8)t = (5/8)t . . . . . . . subtract 1/8t
15(8/5) = (8/5)(5/8)t . . . . . . . . . multiply by 8/5 (the inverse of 5/8)
24 = t
The tank holds 24 gallons.
