Adam pays $2.70 for a marble and a sticker.
The marble costs 8 times as much as the sticker.
- What is the cost of 1 marble?
- How much is the cost of 2 stickers and 3 marbles?
(a)
Cost of a sticker = 1 u
Cost of a marble = 8 u
Total cost of a sticker and a marble
= 1 u + 8 u
= 9 u
9 u = 2.70
1 u = 2.70 ÷ 9 = 0.30
Cost of the marble
= 8 u
= 8 x 0.30
= $2.40
(b)
Cost of 2 stickers and 3 marbles
= 2 x 1 u + 3 x 8 u
= 2 u + 24 u
= 26 u
= 26 x 0.30
= $7.80
Answer(s): (a) $2.40; (b) $7.80