The number of orange staplers is four times the number of red staplers. The number of red staplers is 9 more than the number of yellow staplers. The total number of staplers is 123. The cost of each orange stapler is $4.30 and the cost of each yellow stapler is $3.10. The total cost of all the staplers is $471.50.
- Find the number of yellow staplers.
- Find the cost of a red stapler.
(a)
Number of yellow staplers = 1 u
Number of red staplers = 1 u + 9
Number of orange staplers
= 4(1 u + 9)
= 4 u + 36
Total of number of staplers
= 1 u + 1 u + 9 + 4 u + 36
= 6 u + 45
6 u + 45 = 123
6 u = 123 - 45
6 u = 78
1 u = 78 ÷ 6 = 13
Number of yellow staplers
= 1 u
= 13
(b)
Number of yellow staplers = 13
Number of red staplers
= 13 + 9
= 22
Number of orange staplers
= 4 x 22
= 88
Cost of yellow staplers
= 13 x 3.10
= $40.30
Cost of orange staplers
= 88 x 4.30
= $378.40
Cost of red staplers
= 471.50 - 378.40 - 40.30
= $52.80
Cost of 1 red stapler
= 52.80 ÷ 22
= $2.40
Answer(s) (a) 13; (b) $2.40
