Adam pays $32.30 for 1 marble and 6 stickers.
The marble costs $1.50 more than each sticker.
- What is the cost of 1 marble?
- How much is the cost of 6 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 + 1.50
Cost of 6 stickers
= 6 x 1 u
= 6 u
Total cost of 1 marble and 6 stickers
= 1 u + 1.50 + 6 u
= 7 u + 1.50
7 u + 1.50 = 32.30
7 u = 32.30 - 1.50
7 u = 30.80
1 u = 30.80 ÷ 7 = 4.40
Cost of 1 marble
= 4.40 + 1.50
= $5.90
(b)
Cost of 6 marbles and 8 stickers
= 6 x 5.90 + 8 x 4.40
= 35.40 + 35.20
= $70.60
Answer(s): (a) $5.90; (b) $70.60