Question

Consider a limousine that gets m(v)= (120 - 2v) / 5 miles per gallon at speed v , whose chauffeur is paid $15/hour, and gas costs $3.5/gallon.
a. Write the function that finds the cost per mile at speed v
b. What speed results in the most inexpensive driving speed?

Answer 1

Answer:

(17.5 / 120 - 2v) + (15 / v)

Step-by-step explanation:

Given : m(v)= (120 - 2v) / 5 miles per gallon at speed v ,

chauffeur is paid $15/hour

gas cost = $3.5/gallon.

Gasoline cost per mile :

Cost per gallon = $3.5

Cost per gallon * 1/(m(v))

$3.5 * 1 / (120 - 2v) / 5

$3.5 * 5 / 120 - 2 v

= 17.5 / 120 - 2v

Time = distance / speed

Chauffeur cost = 15 per hour / v

Hence ;

Total cost :

Cost of gasoline + Cost of chauffeur

(17.5 / 120 - 2v) + (15 / v)