Adam spends $15.50 on 3 beads and 4 marbles.
A bead costs $1.90 more than 1 marble.
- How much does 1 bead cost?
- How much do 5 beads cost?
- How much do a marble and 5 beads cost?
- How much do 5 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 3 beads and 4 marbles
= 3(1 u + 1.90) + 4 u
= 3 u + 5.70 + 4 u
= 3 u + 4 u + 5.70
= 7 u + 5.70
7 u + 5.70 = 15.50
7 u = 15.50 - 5.70
7 u = 9.80
1 u = 9.80 ÷ 7 = 1.40
Cost of 1 bead
= 1 u + 1.90
= 1.40 + 1.90
= $3.30
(b)
Cost of 5 beads
= 5 x 3.30
= $16.50
(c)
Cost of 1 marble and 5 beads
= 1.40 + 16.50
= $17.90
(d)
Cost of 5 beads more than 1 marble
= 16.50 - 1.40
= $15.10
Answer(s): (a) $3.30; (b) $16.50; (c) $17.90; (d) $15.10
