Adam spends $16.30 on 2 beads and 3 marbles.
A bead costs $1.90 more than 1 marble.
- How much does 1 bead cost?
- How much do 8 beads cost?
- How much do a marble and 8 beads cost?
- How much do 8 beads cost more than 1 marble?
(a)
Let the cheaper item be 1 u.
Cost of 1 marble = 1 u
Cost of 1 bead = 1 u + 1.90
Total cost of 2 beads and 3 marbles
= 2(1 u + 1.90) + 3 u
= 2 u + 3.80 + 3 u
= 2 u + 3 u + 3.80
= 5 u + 3.80
5 u + 3.80 = 16.30
5 u = 16.30 - 3.80
5 u = 12.50
1 u = 12.50 ÷ 5 = 2.50
Cost of 1 bead
= 1 u + 1.90
= 2.50 + 1.90
= $4.40
(b)
Cost of 8 beads
= 8 x 4.40
= $35.20
(c)
Cost of 1 marble and 8 beads
= 2.50 + 35.20
= $37.70
(d)
Cost of 8 beads more than 1 marble
= 35.20 - 2.50
= $32.70
Answer(s): (a) $4.40; (b) $35.20; (c) $37.70; (d) $32.70