Adam pays $10.70 for 2 beads and 3 marbles.
A bead costs $4.60 more than 1 marble.
What is the cost of 4 beads and 3 marbles?
Choose the cheaper item to be 1 u.
1 bead costs $4.60 more than 1 marble.
The cheaper item is the marble.

Cost of the marble = 1 u
Cost of the bead = 1 u + 4.60

Cost of 2 beads = 2 x (1 u + 4.60) = 2 u + 9.20
Cost of 3 marbles = 3 u

Total cost of 2 beads and 3 marbles
= 2 u + 9.20 + 3 u
= 2 u + 3 u + 9.20
= 5 u + 9.20

5 u + 9.20 = 10.70
5 u = 10.70 - 9.20
5 u = 1.50

1 u = 1.50 ÷ 5 = 0.30

Cost of 4 beads and 3 marbles
= 4 x (1 u + 4.60) + 3 u
= 4 u + 18.40 + 3 u
= 4 u + 3 u + 18.40
= 7 u + 18.40
= 7 x 0.30 + 18.40
= 2.10 + 18.40
= $20.50

Answer(s): $20.50