How do you convert $ 240 $ miles per hour to feet per second?

Hint: Convert the given value in the required specific units by using the conversion equation. Use the formula - $ 1{\text{ mile}} = 5280{\text{ feet}} $ and $ 1{\text{ hour = 3600 seconds}} $ Place the relation for the given number and simplify the equation using the basic mathematical calculations.

Complete step-by-step answer:
We know the basic relation between miles and feet.
 $ 1{\text{ mile}} = 5280{\text{ feet}} $
 $ 1{\text{ hour = 3600 seconds}} $
Convert $ 240 $ miles to feet
 $ {\text{240 mile}} = 240 \times 5280{\text{ feet}} $
Simplify the above equation finding the product of the terms in the above expression –
 $ {\text{240 mile}} = 1267200{\text{ feet}} $
Now, miles to feet per second is given by –
 $ = \dfrac{{1267200{\text{ }}}}{{3600}} $ feet per second
Simplify the above expression finding the common factors from the numerator and the denominator.
 $ = 352 $ feet per second
This is the required solution.
So, the correct answer is “ $ 352 $ feet per second”.

Note: It is very important to know the difference between the system of units and the conversional ratios between them. Since if we say mass of one it does not make any sense, also length of one feet and one meter differs a lot.