Adam pays $33.10 for 1 marble and 5 stickers.
The marble costs $1.90 more than each sticker.
- What is the cost of 1 marble?
- How much is the cost of 5 marbles and 6 stickers?
(a)
Choose the cheaper item to be 1 u.
Cost of 1 sticker = 1 u
Cost of 1 marble = 1 u + 1.90
Cost of 5 stickers
= 5 x 1 u
= 5 u
Total cost of 1 marble and 5 stickers
= 1 u + 1.90 + 5 u
= 6 u + 1.90
6 u + 1.90 = 33.10
6 u = 33.10 - 1.90
6 u = 31.20
1 u = 31.20 ÷ 6 = 5.20
Cost of 1 marble
= 5.20 + 1.90
= $7.10
(b)
Cost of 5 marbles and 6 stickers
= 5 x 7.10 + 6 x 5.20
= 35.50 + 31.20
= $66.70
Answer(s): (a) $7.10; (b) $66.70