Adam pays $44.40 for 1 marble and 6 stickers.
The marble costs $1.70 more than each sticker.
- What is the cost of 1 marble?
- How much is the cost of 6 marbles and 5 stickers?
(a)
Choose the cheaper item to be 1 u.
Cost of 1 sticker = 1 u
Cost of 1 marble = 1 u + 1.70
Cost of 6 stickers
= 6 x 1 u
= 6 u
Total cost of 1 marble and 6 stickers
= 1 u + 1.70 + 6 u
= 7 u + 1.70
7 u + 1.70 = 44.40
7 u = 44.40 - 1.70
7 u = 42.70
1 u = 42.70 ÷ 7 = 6.10
Cost of 1 marble
= 6.10 + 1.70
= $7.80
(b)
Cost of 6 marbles and 5 stickers
= 6 x 7.80 + 5 x 6.10
= 46.80 + 30.50
= $77.30
Answer(s): (a) $7.80; (b) $77.30