A pencil cost $2.50. A notebook cost $15.50 more than the pencil. Opal spent $138 on such pencils and notebooks. She bought twice as many pencils as notebooks.
- How many notebooks did Opal buy?
- How much money did Opal spend on the pencils?
|
Pencils |
Notebooks |
Total |
Number |
2 u |
1 u |
|
Value |
2.50 |
18 |
|
Total value |
5 u |
18 u |
138 |
(a)
Cost of a notebook
= 15.50 + 2.50
= $18
Total cost of pencils and notebooks
= 5 u + 18 u
= 23 u
23 u = 138
1 u = 138 ÷ 23 = 6
Number of notebooks that Opal bought
= 1 u
= 6
(b)
Amount that Opal spent on pencils
= 5 u
= 5 x 6
= $30
Answer(s): (a) 6; (b) $30