At a shop, Lilian paid $16 for 1 magazine and 3 story books. The magazine cost $7 more than the total cost of all the story books.
- How much did 1 magazine cost?
- How much did 1 story book cost?
(a)
Cost of 3 story books = 1 u
Cost of 1 magazine = 1 u + 7
Total cost of 3 story books and 1 magazine
= 1 u + 1 u + 7
= 2 u + 7
2 u + 7 = 16
2 u = 16 - 7
2 u = 9
1 u = 9 ÷ 2 = 4.50
Cost of 1 magazine
= 1 u + 7
= 4.50 + 7
= $11.50
(b)
Cost of 3 story books = $4.50
Cost of 1 story book
= 4.50 ÷ 3
= $1.50
Answer(s): (a) $11.50; (b) $1.50