Consider the amount of gas in your car during a road trip. You start out with 45 gallons and drive for 4 hours, leaving you with 27 gallons in the tank. You stop for lunch for 2 hours and then drive for 2 more hours, leaving you with 18 gallons.

Question

t= time

C (t)=_____ if 0 </ t </ 4

C (t)=_____ if 4 < t </ 6

C (t)=_____ if 6 < t </ 8

Answer 1

I'll do one:

C(t) = 45 - (45-27)/4 * 4 - (27-18)/2 * (t-6)
= 27 - 9/2 (t-6)
= 54 - 9/2 t if 6 < t <= 8

This should give a clue to the other parts...

Answer 2

45-4.5t