Adam spends $15.90 on 5 beads and 6 marbles.
A bead costs $2.30 more than 1 marble.
- How much does 1 bead cost?
- How much do 6 beads cost?
- How much do a marble and 6 beads cost?
- How much do 6 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 + 2.30
Total cost of 5 beads and 6 marbles
= 5(1 u + 2.30) + 6 u
= 5 u + 11.50 + 6 u
= 5 u + 6 u + 11.50
= 11 u + 11.50
11 u + 11.50 = 15.90
11 u = 15.90 - 11.50
11 u = 4.40
1 u = 4.40 ÷ 11 = 0.40
Cost of 1 bead
= 1 u + 2.30
= 0.40 + 2.30
= $2.70
(b)
Cost of 6 beads
= 6 x 2.70
= $16.20
(c)
Cost of 1 marble and 6 beads
= 0.40 + 16.20
= $16.60
(d)
Cost of 6 beads more than 1 marble
= 16.20 - 0.40
= $15.80
Answer(s): (a) $2.70; (b) $16.20; (c) $16.60; (d) $15.80