The cost of n people staying in a motel is given by the formula:
cost ($) =75+15n
a) find the cost for 3 people
b) find the cost for 1 person
c) find the cost for a team of 15
d) if a group spent $165 on one night's accommodation, how many were in the group?

Bsically, you subsitute and multiply
c=75+15n
a
for 3 people
subsitute 3 for n
c=75+15(3)
c=75+45
c=120
cost for 3 people is 120

B
1 person
c=75+15(1)
c=75+15
c=90
cost for 1 person is 90

C
15 poepls is
c=75+15(15)
c=75+225
c=300
300 people for 15 people

D
so if cost is 165
c=165
165=75+15n
subtract 75 from both sides
90=15n
divide by 15
6=n
6 people

the answers:
a.$120
b.$90
c.$300
d. 6 people

A). 75 + 15 (3) = 75 + 45 = $120. / / / b). 75 + 15 (1) = 75 + 15 = $90. / / / c). 75 + 15 (15) = 75 + 225 = $300. / / / d). 75 + 15N = 165. Subtract 75 from each side: 15N = 90. Divide each side by 15: N = 90/15 = 6 people in the group.

I'm pretty sure it's b). i try drawing the functions out and b is the one that stands out or isnt a "line"