Answer: Change = - 2.8 gallons
Explanation:
Let X be the starting amount of paint in the can, in gallons.
"Removes 5/8 gallon" can be written -(5/8)gal
"Adds 3/8 gallon" becomes +(3/8)gal
The result is : X - (5/8)gal + (3/8)gal = Remaining Paint (gallons)
Consolidating: Remaining (gallons) = X - (2/8)gal
If we want the overall increase/decrease, subtract the initial volume:
Initial - Remaining = Change in amount of paint in can
Change = (X-(2/8)gal) - X = - (2/8) gallons