Harold has $20.00 to spend. He decided to buy a shirt for $15.95 and spend the rest on packs of gum.
If each pack of gum costs $1.99, how many packs of gum can Harold buy?
Harold spends $15.95 on a shirt, so he has $20.00 - $15.95 = $<<20-15.95=4.05>>4.05 left to spend on gum.
Each pack of gum costs $1.99, so Harold can buy $4.05 / $1.99 = 2.034170 times the number of packs of gum.
Since you cannot purchase a fraction of a pack of gum, Harold can buy 2 packs of gum. Answer: \boxed{2}.