Question

Miss David's birthday is in April, and she is going to have a party. She is looking to buy a bag of decorations. Each bag has two different types of decorations: balloons and streamers. The first bag has 11 balloons and 6 streamers. The second bag has 15 balloons and 4 streamers. The last bag has 6 balloons and 12 streamers. Bag 1 costs $91, bag 2 costs $99, and bag 3 costs $102. How much does each type of decoration cost?

Answer 1

b = $5

s = $6

Explanation:

this can be solved using simultaneous equation

s = streamers

b = balloons

either of the 3 equations can be used to determine the price of the items

11b + 6s = 91 equation 1

15b + 4s = 99 equation 2

multiply equation 1 by 4 and equation 2 by 6

44b + 24s = 364 eqn 3

90b + 24s = 594 eqn 4

subtract equation 3 from 4

230 = 46b

b = 5

substitute for b in eqn 1

55 + 6s = 91

s = 6