Jared bought 7 cans of paint. A can of red paint costs $3.75. A can of black paint costs $2.75. Jared spent $22.25 in all. How many cans of black (b) and how many cans of red (r) did hé buy?
a = # A cans
b = # B cans = 7 - a
3.75 a + 2.75 (7-a) = 22.25 solve for 'a' , the # A cans then Bcans = 7-a