Gillian spent $230 on some notebooks, files and markers. The number of notebooks she bought was ¹₂ the number of files. The number of markers she bought was ²₅ the number of files. The ratio of the amount of money she spent on the notebooks, files and markers was 9 : 8 : 6. The files were sold at 4 for $8. Find the price of 1 notebook.

Amount spent
Notebooks	Files	Markers	Total
9 u	8 u	6 u	$230

Total amount that Gillian spent on notebooks, files and markers
= 9 u + 8 u + 6 u
= 23 u

23 u = 230

1 u = 230 ÷ 23 = 10

Amount that Gillian spent on files
= 8 u
= 8 x 10
= $80

Number of sets of files of 4 bought
= 80 ÷ 8
= 10

Number of files that Gillian bought
= 10 x 4
= 40

Number of items bought
Notebooks	Files	Markers	Total
1x5	2x5
	5x2	2x2
5 p	10 p	4 p	19 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 Gillian bought = 10 p

10 p = 40

1 p = 40 ÷ 10 = 4

Number of notebooks that Gillian bought
= 5 p
= 5 x 4
= 20

Amount that Gillian spent on notebooks
= 9 u
= 9 x 10
= $90

Price of 1 notebook
= 90 ÷ 20
= $4.50

Answer(s): $4.50