Emily spent $100 on some notebooks, pencils and staplers. The number of notebooks she bought was ¹₂ the number of pencils. The number of staplers she bought was ³₄ the number of pencils. The ratio of the amount of money she spent on the notebooks, pencils and staplers was 5 : 8 : 7. The pencils were sold at 5 for $10. Find the price of 1 notebook.

Amount spent
Notebooks	Pencils	Staplers	Total
5 u	8 u	7 u	$100

Total amount that Emily spent on notebooks, pencils and staplers
= 5 u + 8 u + 7 u
= 20 u

20 u = 100

1 u = 100 ÷ 20 = 5

Amount that Emily spent on pencils
= 8 u
= 8 x 5
= $40

Number of sets of pencils of 5 bought
= 40 ÷ 10
= 4

Number of pencils that Emily bought
= 4 x 5
= 20

Number of items bought
Notebooks	Pencils	Staplers	Total
1x2	2x2
	4x1	3x1
2 p	4 p	3 p	9 p

The number of pencils bought is repeated.  Make the number of pencils bought is the same.  LCM of 2 and 4 is 4.

Number of pencils that Emily bought = 4 p

4 p = 20

1 p = 20 ÷ 4 = 5

Number of notebooks that Emily bought
= 2 p
= 2 x 5
= 10

Amount that Emily spent on notebooks
= 5 u
= 5 x 5
= $25

Price of 1 notebook
= 25 ÷ 10
= $2.50

Answer(s): $2.50