Answer:
the price of the drink to the nearest cent is $2.50
Step-by-step explanation:
1 bag of popcorn = b
1 drink = d
Amelia spends this:
6b + 3d = 18.00
6b = 18 - 3d
b = 18/6 -3d/6
b = 3 - 1/2*d
Nora spends this:
5b + 9d = 31.25
9d = 31.25 - 5b
d = 31.25/9 -5/9*b
now substitute d = 31.25/9 -5/9*b in b = 3 - 1/2*d
d = 31.25/9 -5/9*(3 - 1/2*d)
d = 31.25/9 -15/9 + 5/18d
18/18d - 5/18d = 31.25/9 -15/9
13/18d = 31.25/9 -15/9
d = 18/13 * ( 31.25/9 -15/9 )
d = 2,5
The price of a drink is $2.50
EXTRA
now substitute d = 2,5 in b = 3 - 1/2*d
b = 3 - 1/2*(2.5)
b = 3 - 1.25
b = 1.75
The price of a bag of popcorn is $1.75