Adam pays $22.70 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 2 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 = 22.70
6 u = 22.70 - 1.10
6 u = 21.60
1 u = 21.60 ÷ 6 = 3.60
Cost of 1 marble
= 3.60 + 1.10
= $4.70
(b)
Cost of 5 marbles and 2 stickers
= 5 x 4.70 + 2 x 3.60
= 23.50 + 7.20
= $30.70
Answer(s): (a) $4.70; (b) $30.70