A local hamburger shop sold a combined total of 605 hamburgers and cheeseburgers on Friday. There were 55 more cheeseburgers sold than hamburgers. How many hamburgers were sold on Friday?

H + c = 605

c = h + 55

h + h + 55 = 605

2h + 55 = 605

2h = 605 - 55

2h = 550

h = 550/2

h = 275 < = = there were 275 hamburgers sold on Friday

c = h + 55

c = 275 + 55

C = 330 ... there were 330 cheeseburgers sold on Friday