Question 86746
The speed express in terms of distance over time  S = D/T

---Step#1:  Calculating Speed
In this case the cart travele 1/4 miles in 13.6 sec.
So S=(0.25 miles ) / (13.6 sec)

---Step#2:  Converting to MPH
In most cases speed is discribed as mph or miles-per-hour.
Solve this conversion

{{{S=(0.25miles/13.6sec)*(60sec/1minute)*(60minutes/1hour) }}}

******Notice how the sec. and minutes cancel out and only the hour remain****