10k^4+10k^3+8k^2+8k+10/k+1 not sure if this is what you are looking for or not hope it helps
(a) d=days C=cost
d C
1 30
2 40
3 50
4 60
C=10(d-1)+30
(b) C=10(5-1)+30
C=40+30
C=70
P/90 = 4/18
18P = 90*4 [cross-multiplication]
P = 360/18
P = 20
So, answer is P equals to 20
Well what do u need help with can u explain?
