At a stationery shop, David paid $15 for 1 colouring book and 3 magazines. The colouring book cost $6 more than the total cost of all the magazines.
- How much did 1 colouring book cost?
- How much did 1 magazine cost?
(a)
Cost of 3 magazines = 1 u
Cost of 1 colouring book = 1 u + 6
Total cost of 3 magazines and 1 colouring book
= 1 u + 1 u + 6
= 2 u + 6
2 u + 6 = 15
2 u = 15 - 6
2 u = 9
1 u = 9 ÷ 2 = 4.50
Cost of 1 colouring book
= 1 u + 6
= 4.50 + 6
= $10.50
(b)
Cost of 3 magazines = $4.50
Cost of 1 magazine
= 4.50 ÷ 3
= $1.50
Answer(s): (a) $10.50; (b) $1.50