Mr. harper's car used 5 gallons of gasoline to travel 150 miles. after he had some work done on the cars engine ,it used it used 6 gallons of gasoline to travel 210 miles. if the price of gasoline was $3.50 per gallon, how much money did mr. harper save per mile after the work was done on the cars engine? (round your answers to the nearest cent.)

He saves $0.0175 per mile

Step-by-step explanation:

Before the work done on the car´s engine, it took 0.033 gallons to travel one mile ( 5 gallons /150miles =0.033). After this work, the car spends 0.028 gallons to travel one mile (6 gallons/210 miles =0.028). The difference between this two is:

0.033 gallons/mile-0.028 gallons/mile= 0.005 gallons per mile.

Now Mr.Harper´s saves 0.005 gallons per mile.

In money he saves:

$3,50/gallon*0.005 gallon/mile= $0.0175/mile (the unit of "gallon" cancel each other)

Rounded to the nearest cent:

He saves $0.0 per mile.

the answer is:

the correct option is the option b.

to calculate the surface area of the right cylinder, we need to use the following formula:

from the picture we know that:

so, substituting and calculting we have:

hence, we have that the correct option is the option b.

have a nice day!