Question

If henry were to add 5 gallons of water to a tank that is already 34 full of water, the tank would be 78 full. how many gallons of water would the tank hold if it were full?

Answer 1

Please express those fractions properly:  3/4, 7/8.

Let g be the # of gallons the tank could hold when full.  

Then (3/4)n + 5 = (7/8)n.  

solving for n:  Mult all 3 terms by the LCD (8):  6n + 5(8) = 7n.

Then n=5(8) = 40 (gallons).  The tank would hold 40 gallons of water were it full.