Answer:
The cost for 58 minutes is $14.74
Step-by-step explanation:
Assuming that the graph of cost versus time varies linearly,
the given 2 coordinates are (45,13.31) and (74,16.50).
Let the cost for 58 minutes be "y".
The third coordinate is (58, y) , which lies on the line joining the above 2 points.
The slope of the line is
m = [tex]\frac{(16.50)-(13.31)}{(74)-(45)}[/tex]
m = 0.11
The equation of line is,
[tex](Y - 13.31) = m(X - 45)[/tex]
[tex](Y - 13.31) = (0.11)(X - 45)[/tex]
Inserting third point in above equation, we get,
[tex](Y - 13.31) = (0.11)(58- 45)[/tex]
[tex]Y = 14.74[/tex]
Thus, the cost for 58 minutes is $14.74
