Question

The math team sold 42 hamburger meals and 15 ribs meals at the pep rally for a total of $243. At the game that night they sold 36 hamburger meals and 30 ribs meals for a total of $294. What is the cost of 1 rib meal?

Answer 1

42h+15r=243
36h+30r=294

Answer 2

Let one hamburger meal costs x and one rib meal costs y..

So, according to the question :

42x + 15y = 243 -----------1
36x + 30y = 294

The lower equation can be more simplified by dividing by 2 both sides:
18x + 15y = 147 ------------2

Therefore, subtract equation 1 and equation 2,

24x = 96

So, x = 4

Put value of x in any one equation to get the value of y:
15y = 147 - 18x
15y = 147 - 18(4)
15y = 147 - 72
15y = 75

Therefore y = 5..

Therefore, cost of 1 rib meal (y) is $5...