At a bookstore, Bryan paid $13 for 1 guide book and 3 story books. The guide book cost $4 more than the total cost of all the story books.
- How much did 1 guide book cost?
- How much did 1 story book cost?
(a)
Cost of 3 story books = 1 u
Cost of 1 guide book = 1 u + 4
Total cost of 3 story books and 1 guide book
= 1 u + 1 u + 4
= 2 u + 4
2 u + 4 = 13
2 u = 13 - 4
2 u = 9
1 u = 9 ÷ 2 = 4.50
Cost of 1 guide book
= 1 u + 4
= 4.50 + 4
= $8.50
(b)
Cost of 3 story books = $4.50
Cost of 1 story book
= 4.50 ÷ 3
= $1.50
Answer(s): (a) $8.50; (b) $1.50