Do 19 divided by 1.5 and you get 12.6666667 repeating. But she needs about 12 cups
C.
24 means that you earned 6 dollars an hour for 4 hours. 2.5n means that for every person, n, you receive an additional $2.50.
Step-by-step explanation:

multiply both sides of the equation by 3.
2x+3y=9
move variable to the right side and change its sign
2x=9-3y
divide both sides of the equation by 2
x=9/2-3/2y