Adam pays $8.60 for 2 stickers and 4 beads.
A sticker costs $3.40 more than 1 bead.
What is the cost of 3 stickers and 2 beads?
Choose the cheaper item to be 1 u.
1 sticker costs $3.40 more than 1 bead.
The cheaper item is the bead.

Cost of the bead = 1 u
Cost of the sticker = 1 u + 3.40

Cost of 2 stickers = 2 x (1 u + 3.40) = 2 u + 6.80
Cost of 4 beads = 4 u

Total cost of 2 stickers and 4 beads
= 2 u + 6.80 + 4 u
= 2 u + 4 u + 6.80
= 6 u + 6.80

6 u + 6.80 = 8.60
6 u = 8.60 - 6.80
6 u = 1.80

1 u = 1.80 ÷ 6 = 0.30

Cost of 3 stickers and 2 beads
= 3 x (1 u + 3.40) + 2 u
= 3 u + 10.20 + 2 u
= 3 u + 2 u + 10.20
= 5 u + 10.20
= 5 x 0.30 + 10.20
= 1.50 + 10.20
= $11.70

Answer(s): $11.70