At a book shop, Jackson paid $18 for 1 novel and 3 colouring books. The novel cost $3 more than the total cost of all the colouring books.
- How much did 1 novel cost?
- How much did 1 colouring book cost?
(a)
Cost of 3 colouring books = 1 u
Cost of 1 novel = 1 u + 3
Total cost of 3 colouring books and 1 novel
= 1 u + 1 u + 3
= 2 u + 3
2 u + 3 = 18
2 u = 18 - 3
2 u = 15
1 u = 15 ÷ 2 = 7.50
Cost of 1 novel
= 1 u + 3
= 7.50 + 3
= $10.50
(b)
Cost of 3 colouring books = $7.50
Cost of 1 colouring book
= 7.50 ÷ 3
= $2.50
Answer(s): (a) $10.50; (b) $2.50