If we assume the number of polo shirts have been sold is x, the number of casual shirts have been sold will be 4x.
x*18+4x*9=$1080
(18+36)x=$1080
54x=$1080
x=20
The number of casual shirts have been sold is 4*20=80
85 = 10x+15
70 = 10x
x = 7
180-85 = 95 = z
93.86 is your answer.
I hope this helps!
What? I don't understand what you mean...
