Adam buys a marble for $6.
He also buys a bead.
The bead costs 3 times as much as the marble.
- How much less does the bead cost than the marble?
- How much does he spend altogether?
- How much are 3 beads?
- How much are 4 beads and 4 marbles?
(a)
Choose the cheaper item to be 1 u.
The bead costs 3 times as much as the marble.
The marble is cheaper.
Cost of the marble = 1 u = $6
Cost of the bead = 3 u
Amount that the marble costs less than the bead
= 3 u - 1 u
= 2 u
= 2 x 6
= $12
(b)
Total amount that Adam spends
= 1 u + 3 u
= 4 u
= 4 x 6
= $24
(c)
Cost of 3 beads
= 3 x 3 u
= 9 u
= 9 x 6
= $54
(d )
Cost of 4 beads and 4 marbles
= 4 x 3 u + 4 x 1 u
= 12 u + 4 u
= 16 u
= 16 x 6
= $96
Answer(s): (a) $12; (b) $24; (c) $54; (d) $96