Adam pays $24.40 for 1 marble and 5 stickers.
The marble costs $2.20 more than each sticker.
- What is the cost of 1 marble?
- How much is the cost of 5 marbles and 7 stickers?
(a)
Choose the cheaper item to be 1 u.
Cost of 1 sticker = 1 u
Cost of 1 marble = 1 u + 2.20
Cost of 5 stickers
= 5 x 1 u
= 5 u
Total cost of 1 marble and 5 stickers
= 1 u + 2.20 + 5 u
= 6 u + 2.20
6 u + 2.20 = 24.40
6 u = 24.40 - 2.20
6 u = 22.20
1 u = 22.20 ÷ 6 = 3.70
Cost of 1 marble
= 3.70 + 2.20
= $5.90
(b)
Cost of 5 marbles and 7 stickers
= 5 x 5.90 + 7 x 3.70
= 29.50 + 25.90
= $55.40
Answer(s): (a) $5.90; (b) $55.40