Question

At the movies, you buy 3 bags of popcorn and 2 soft drinks and it costs you $16.50. Layne buys 2 bags of popcorn and 1 soft drink and his total is $10.25. Find the cost of one bag of popcorn and one soft drink.

Answer 1

Popcorn= $4.5

Soft drink= $1.5

Explanation:

Let p represent the cost of popcorn and let a represent the cost of soft drinks

3p + 2s= 16.50

2p + s= 10.5

Multiply equation 1 by 2 and equation 2 by 3

6p + 4s = 33

-

6p + 3s = 31.5

s= 1.5

Substitute 1.5 for s in equation 1

3p + 2s = 16.50

3p + 2(1.5)= 16.50

3p + 3 = 16.50

3p = 16.50-3

3p = 13.5

p = 13.5/3

p = 4.5

Hence the price of a bah of popcorn is $4.5 and soft drink is $1.5