Adam pays $3.40 for 2 beads and 4 stickers.
A bead costs $1.40 more than 1 sticker.
What is the cost of 3 beads and 2 stickers?
Choose the cheaper item to be 1 u.
1 bead costs $1.40 more than 1 sticker.
The cheaper item is the sticker.

Cost of the sticker = 1 u
Cost of the bead = 1 u + 1.40

Cost of 2 beads = 2 x (1 u + 1.40) = 2 u + 2.80
Cost of 4 stickers = 4 u

Total cost of 2 beads and 4 stickers
= 2 u + 2.80 + 4 u
= 2 u + 4 u + 2.80
= 6 u + 2.80

6 u + 2.80 = 3.40
6 u = 3.40 - 2.80
6 u = 0.60

1 u = 0.60 ÷ 6 = 0.10

Cost of 3 beads and 2 stickers
= 3 x (1 u + 1.40) + 2 u
= 3 u + 4.20 + 2 u
= 3 u + 2 u + 4.20
= 5 u + 4.20
= 5 x 0.10 + 4.20
= 0.50 + 4.20
= $4.70

Answer(s): $4.70