Adam pays $26 for 4 marbles and 3 beads.
9 marbles cost as much as 3 beads.
- How much is 1 marble?
- How much is 1 bead?
- How much is 5 beads and 3 marbles?
(a)
Choose the smaller group to be 1 u.
Cost of 9 marbles = Cost of 3 beads
Cost of 3 marbles = Cost of 1 bead
Cost of 1 marble = 1 u
Cost of 1 bead = 3 u
Cost of 4 marbles
= 4 x 1 u
= 4 u
Cost of 3 beads
= 3 x 3 u
= 9 u
Total cost of 4 marbles and 3 beads
= 4 u + 9 u
= 13 u
13 u = 26
1 u = 26 ÷ 13 = 2
Cost of 1 marble = 1 u = $2
(b)
Cost of 1 bead
= 3 u
= 3 x 2
= $6
(c)
Cost of 5 beads and 3 marbles
= 5 x 3 u + 3 x 1 u
= 15 u + 3 u
= 18 u
= 18 x 2
= $36
Answer(s): (a) $2; (b) $6; (c) $36