We are asked to find out whether 120 lb to 180 lb is an increase or decrease?
Since the final amount (180 lb) is greater than the initial amount (120 lb) the difference will be positive.
A positve difference indictes an increase.
[tex]difference=180\: lb-120\: lb=60\: lb[/tex]Therefore, the difference is positive (that is 60 lb) and it is an increase.
