The problem is multiplying w by 18 to get a total of 108.
The answer would be :
D If one full glass holds 18 ounces of water, how many full glasses will hold 108 ounces?
To solve for the number of cups divide both sides of the equation by 18:
18w = 108
W= 108 / 18
W = 6
It would take 6 18 ounce glasses to equal 108 total ounces.