Answer:
1) one muffin costs $1.50
one quart of milk costs $3.00
2) 10 videos, 30 CDs
Explanation:
1)
m = cost of one muffin
q = cost of one quart of milk
System of equations:
3m + 1q = 7.5
8m + 2q = 18
I multiplied the first equation by -2 to eliminate the 'q' values
-6m - 2q = -15
+ 8m + 2q = 18
2m = 3
m = 3/2
find 'q':
3(3/2) + q = 7.5
9/2 + q = 15/2
q = 6/2 or 3
2)
c = # of CDs sold
v = # of videos sold
System of equations:
c + v = 40
4c + 6v = 180
I solved first equation for 'c' to get c = 40 - v
4(40-v) + 6v = 180
160 - 4v + 6v = 180
2v = 20
v = 10
10 + c = 40
c = 30