Adam pays $27.60 for a marble, a bead and a sticker.
The marble costs $2.20 less than the bead.
The bead costs $1.60 less than the sticker.
What is the cost of 8 stickers more than 6 marbles?
Choose the cheapest item to be 1 u.

Cost of the marble = 1 u
Cost of the bead = 1 u + 2.20
Cost of the sticker = 1 u + 2.20 + 1.60 = 1 u + 3.80

Total cost of the marble, the bead and the sticker
= 1 u + 1 u + 2.20 + 1 u + 3.80
= 3 u + 6.00

3 u + 6.00 = 27.60
3 u = 27.60 - 6.00
3 u = 21.60

1 u = 21.60 ÷ 3 = 7.20

Cost of 8 stickers more than 6 marbles
= 8 x (1 u + 3.80) - 6 x 1 u
= 8 u + 30.40 - 6 u
= 2 u + 30.40
= 2 x 7.20 + 30.40
= 14.40 + 30.40
= $44.80

Answer(s): $44.80