At a bookstore, Henry paid $17 for 1 guide book and 2 colouring books. The guide book cost $4 more than the total cost of all the colouring books.
- How much did 1 guide book cost?
- How much did 1 colouring book cost?
(a)
Cost of 2 colouring books = 1 u
Cost of 1 guide book = 1 u + 4
Total cost of 2 colouring books and 1 guide book
= 1 u + 1 u + 4
= 2 u + 4
2 u + 4 = 17
2 u = 17 - 4
2 u = 13
1 u = 13 ÷ 2 = 6.50
Cost of 1 guide book
= 1 u + 4
= 6.50 + 4
= $10.50
(b)
Cost of 2 colouring books = $6.50
Cost of 1 colouring book
= 6.50 ÷ 2
= $3.25
Answer(s): (a) $10.50; (b) $3.25