Adam buys a sticker for $3.
He also buys a marble.
The marble costs 2 times as much as the sticker.
- How much less does the marble cost than the sticker?
- How much does he spend altogether?
- How much are 4 marbles?
- How much are 5 marbles and 3 stickers?
(a)
Choose the cheaper item to be 1 u.
The marble costs 2 times as much as the sticker.
The sticker is cheaper.
Cost of the sticker = 1 u = $3
Cost of the marble = 2 u
Amount that the sticker costs less than the marble
= 2 u - 1 u
= 1 u
= 1 x 3
= $3
(b)
Total amount that Adam spends
= 1 u + 2 u
= 3 u
= 3 x 3
= $9
(c)
Cost of 4 marbles
= 4 x 2 u
= 8 u
= 8 x 3
= $24
(d )
Cost of 5 marbles and 3 stickers
= 5 x 2 u + 3 x 1 u
= 10 u + 3 u
= 13 u
= 13 x 3
= $39
Answer(s): (a) $3; (b) $9; (c) $24; (d) $39