Tony has 6 dollars

Question

Tony has 6 dollars in change in his car. Every time he drives to visit his grandma, he pays $1.25 in tolls. Write an equation for the amount of money that Tony has after passing through each toll. Complete the table of values for t=0, t=1 and t=4 and then graph the relationship between the number of toll booths and money Tony has.

Answer 1

 

t = trip through toll booth (independent variable: x-axis )

M = money in car (dependent variable: y-axis )

 

M = $6.00 - $1.25t

 

t= 0 

M = 6 - 1.25(0) = $6

plot (0,6)    y-intercept represents $ with 0 trips

 

t=1

M = 6 - 1.25(1) = $4.75

plot (1,4.75)

 

t=4

M = 6 - 1.25(4) = $0

plot (4,0)  x-intercept represents when Tony is out of cash

 

Connect the three points and you will see a linear relationship between money and trips.