Adam pays $44.30 for 1 marble and 5 stickers.
The marble costs $1.10 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 + 1.10
Cost of 5 stickers
= 5 x 1 u
= 5 u
Total cost of 1 marble and 5 stickers
= 1 u + 1.10 + 5 u
= 6 u + 1.10
6 u + 1.10 = 44.30
6 u = 44.30 - 1.10
6 u = 43.20
1 u = 43.20 ÷ 6 = 7.20
Cost of 1 marble
= 7.20 + 1.10
= $8.30
(b)
Cost of 5 marbles and 7 stickers
= 5 x 8.30 + 7 x 7.20
= 41.50 + 50.40
= $91.90
Answer(s): (a) $8.30; (b) $91.90