The insight bus tour offered to take a group of senior citizen to a lake resort for a fare of $120 per person if 25 person or fewer sign up. If more than 25 person make the trip, each fare will be reduced by $20. The capacity of the bus is 40 people. find the total farr revenue function R(x) if x person make the trip.
# i don't know how to find the selling price hmm
R(x) =
120x if x <= 25
100x is 25 < x <= 40