The number of brown folders is thrice the number of yellow folders. The number of yellow folders is 6 more than the number of blue folders. The total number of folders is 109. The cost of each brown folder is $2.50 and the cost of each blue folder is $1.50. The total cost of all the folders is $248.60.
- Find the number of blue folders.
- Find the cost of a yellow folder.
(a)
Number of blue folders = 1 u
Number of yellow folders = 1 u + 6
Number of brown folders
= 3(1 u + 6)
= 3 u + 18
Total of number of folders
= 1 u + 1 u + 6 + 3 u + 18
= 5 u + 24
5 u + 24 = 109
5 u = 109 - 24
5 u = 85
1 u = 85 ÷ 5 = 17
Number of blue folders
= 1 u
= 17
(b)
Number of blue folders = 17
Number of yellow folders
= 17 + 6
= 23
Number of brown folders
= 3 x 23
= 69
Cost of blue folders
= 17 x 1.50
= $25.50
Cost of brown folders
= 69 x 2.50
= $172.50
Cost of yellow folders
= 248.60 - 172.50 - 25.50
= $50.60
Cost of 1 yellow folder
= 50.60 ÷ 23
= $2.20
Answer(s) (a) 17; (b) $2.20
