A painter charges $15.21 per hour, plus an additional amount for the supplies. If he made $187.02 on a job where he worked 7 hours, how much did the supplies cost?

Answer 1

The painter charged a total of $15.21 * 7 = $<<15.21*7=106.47>>106.47 for the hours he worked.
Therefore, the cost of the supplies is $187.02 - $106.47 = $<<187.02-106.47=80.55>>80.55. Answer: \boxed{80.55}.