At a shop, Kylie paid $17 for 1 stamp and 3 marbles. The stamp cost $9 more than each marble.
- How much is 1 marble?
- How much is 1 stamp?
(a)
Cost of 1 marble = 1 u
Cost of 3 marbles = 3 u
Cost of 1 stamp = 1 u + 9
Total cost of 1 stamp and 3 marbles
= 3 u + 1 u + 9
= 4 u + 9
4 u + 9 = 17
4 u = 17 - 9
4 u = 8
1 u = 8 ÷ 4 = 2
Cost of 1 marble
= 1 u
= $2
(b)
Cost of 1 stamp
= 1 u + 9
= 2 + 9
= $11
Answer(s): (a) $2; (b) $11