Adam pays $8.70 for 4 beads and 3 stickers.
A bead costs $1.30 more than 1 sticker.
What is the cost of 2 beads and 3 stickers?
Choose the cheaper item to be 1 u.
1 bead costs $1.30 more than 1 sticker.
The cheaper item is the sticker.

Cost of the sticker = 1 u
Cost of the bead = 1 u + 1.30

Cost of 4 beads = 4 x (1 u + 1.30) = 4 u + 5.20
Cost of 3 stickers = 3 u

Total cost of 4 beads and 3 stickers
= 4 u + 5.20 + 3 u
= 4 u + 3 u + 5.20
= 7 u + 5.20

7 u + 5.20 = 8.70
7 u = 8.70 - 5.20
7 u = 3.50

1 u = 3.50 ÷ 7 = 0.50

Cost of 2 beads and 3 stickers
= 2 x (1 u + 1.30) + 3 u
= 2 u + 2.60 + 3 u
= 2 u + 3 u + 2.60
= 5 u + 2.60
= 5 x 0.50 + 2.60
= 2.50 + 2.60
= $5.10

Answer(s): $5.10