Respuesta :
Given:
An airport limo service charges riders a fixed charge of $15 plus $4.00 per mile.
To find:
Distance in miles must a rider go to have an average cost per mile of $4.60.
Solution:
Let x be the number of miles the rider travel.
Total charges = Fixed charges + Variable charges
According to the question,
Fixed charges = $15
Variable charges = $4x
So, total charges
[tex]T=15+4x[/tex]
Divide the total charges by number of miles to get the cost per mile.
[tex]\text{Cost per mile}=\dfrac{15+4x}{x}[/tex]
Average cost per mile is $4.60.
[tex]4.60=\dfrac{15+4x}{x}[/tex]
[tex]4.60x=15+4x[/tex]
[tex]4.60x-4x=15[/tex]
[tex]0.60x=15[/tex]
Divide both sides by 0.60.
[tex]x=\dfrac{15}{0.60}[/tex]
[tex]x=25[/tex]
Therefore, the required number of miles is 25.
