Adam pays $50 for a marble and a sticker.
The sticker costs four times as much as the marble.
- Find the cost of the marble.
- Find the cost of the sticker.
- Find the difference in the cost of the sticker and the marble.
(a)
Choose the cheaper item to be 1 u.
The sticker costs four times as much as the marble.
The marble is cheaper.
Cost of the marble = 1 u
Cost of the sticker = 4 u
Total cost = 1 u + 4 u = 5 u
5 u = 50
1 u = 50 ÷ 5 = 10
Cost of the marble
= 1 u
= $10
(b)
Cost of the sticker
= 4 u
= 4 x 10
= $40
(c)
Difference in the cost of the sticker and the marble
= 4 u - 1 u
= 3 u
= 3 x 10
= $30
Answer(s): (a) $10; (b) $40; (c) $30