MATH question, please help!!?
1) Find a LINEAR EQUATION that models ticket price (p) as a function of time the ticket has been available (d). P is measured in dollars and d is measured in days.
2) If your ticket to minneapolis costs $25, how long has it been available?
The transportation company Megabus first offers tickets for its Chicago to Minneapolis route 90 days before departure. Each day, the company increases the price of a ticket slightly. When a ticket has been available for 15 days, it costs $17; when a ticket has been available for 60 days, the ticket costs $32.
A linear equation always has the form y = mx + c
Let’s call this equation P = kD + C
P = price of ticket, k = reduction of price per day, D = number of days since available, C = starting price.
You know that when D = 15, P = 17, and when D = 60, P = 32
..So 17 = 15D + C
and 32 = 60D + C ….. …..Subtract these two
….. 15 = 45D
So D = 15/45 = 1/3
Hence 32 = 60/3 + C
C = 32 – 20 = 12
So the equation is P = D/3 + 12
Now all you have to do is put P = 25 and solve for D.
