Mitchell works at a concession stand selling hotdogs and cans of soda. a hotdog costs $3.00 and a can of soda costs $1.00. one night, he notices that he sold a total of 350 items and collected a total of $624.

If you are asking how many hot dogs and cans of soda are sold, this is how I solved it.

Given:
cost of hot dog $3 
cost of a can of soda $1
total items sold: 350
total sales: $624

let h stand for hot dog and s stand for soda.

h + s = 350

3h + 1s = 624

h = 350 - s
3(350-s) + s = 624
1,050 -3s + s = 624
-2s = 624 - 1050
-2s = -426
-2s/-2 = -426/-2
s = 213   cans of soda

h = 350 - s
h = 350 - 213
h = 137 hot dogs

3h + s = 624
3(137) + 213 = 624
411 + 213 = 624
624 = 624

Mitchell sold 137 hot dogs and 213 cans of soda.