Adam pays $23.90 for 1 marble and 4 stickers.
The marble costs $1.40 more than each sticker.
- What is the cost of 1 marble?
- How much is the cost of 4 marbles and 8 stickers?
(a)
Choose the cheaper item to be 1 u.
Cost of 1 sticker = 1 u
Cost of 1 marble = 1 u + 1.40
Cost of 4 stickers
= 4 x 1 u
= 4 u
Total cost of 1 marble and 4 stickers
= 1 u + 1.40 + 4 u
= 5 u + 1.40
5 u + 1.40 = 23.90
5 u = 23.90 - 1.40
5 u = 22.50
1 u = 22.50 ÷ 5 = 4.50
Cost of 1 marble
= 4.50 + 1.40
= $5.90
(b)
Cost of 4 marbles and 8 stickers
= 4 x 5.90 + 8 x 4.50
= 23.60 + 36.00
= $59.60
Answer(s): (a) $5.90; (b) $59.60