Hazel spent $96 on some notebooks, files and pens. The number of notebooks she bought was ¹₂ the number of files. The number of pens she bought was ³₅ the number of files. The ratio of the amount of money she spent on the notebooks, files and pens was 4 : 5 : 7. The files were sold at 4 for $6. Find the price of 1 notebook.

Amount spent
Notebooks	Files	Pens	Total
4 u	5 u	7 u	$96

Total amount that Hazel spent on notebooks, files and pens
= 4 u + 5 u + 7 u
= 16 u

16 u = 96

1 u = 96 ÷ 16 = 6

Amount that Hazel spent on files
= 5 u
= 5 x 6
= $30

Number of sets of files of 4 bought
= 30 ÷ 6
= 5

Number of files that Hazel bought
= 5 x 4
= 20

Number of items bought
Notebooks	Files	Pens	Total
1x5	2x5
	5x2	3x2
5 p	10 p	6 p	21 p

The number of files bought is repeated.  Make the number of files bought is the same.  LCM of 2 and 5 is 10.

Number of files that Hazel bought = 10 p

10 p = 20

1 p = 20 ÷ 10 = 2

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

Amount that Hazel spent on notebooks
= 4 u
= 4 x 6
= $24

Price of 1 notebook
= 24 ÷ 10
= $2.40

Answer(s): $2.40