Julius sold five times as many computers as Sam sold last year. In total, they sold 78 computers. How many computers did Julius sell?

Let x = # of computers sold by Sam; then 5x = # of computers sold by Julius

our equation becomes x + 5x = 78

which becomes 6x = 78

solving, x = 13 which is the # of computers sold by Sam

so 5x = 5 (13) = 65 which is the number of computers sold by Julius