The number of brown folders is thrice the number of blue folders. The number of blue folders is 5 more than the number of orange folders. The total number of folders is 125. The cost of each brown folder is $3.10 and the cost of each orange folder is $3.40. The total cost of all the folders is $383.40.
- Find the number of orange folders.
- Find the cost of a blue folder.
(a)
Number of orange folders = 1 u
Number of blue folders = 1 u + 5
Number of brown folders
= 3(1 u + 5)
= 3 u + 15
Total of number of folders
= 1 u + 1 u + 5 + 3 u + 15
= 5 u + 20
5 u + 20 = 125
5 u = 125 - 20
5 u = 105
1 u = 105 ÷ 5 = 21
Number of orange folders
= 1 u
= 21
(b)
Number of orange folders = 21
Number of blue folders
= 21 + 5
= 26
Number of brown folders
= 3 x 26
= 78
Cost of orange folders
= 21 x 3.40
= $71.40
Cost of brown folders
= 78 x 3.10
= $241.80
Cost of blue folders
= 383.40 - 241.80 - 71.40
= $70.20
Cost of 1 blue folder
= 70.20 ÷ 26
= $2.70
Answer(s) (a) 21; (b) $2.70
