To find the answer, set up an equation:
[tex] \frac{45 \: miles}{1 \: hour} \times \frac{1000 \: meters}{1 \: mile} \times \frac{1 \: hour}{3600 \: seconds} =[/tex]
Using this set up we can cross out the units that are on opposite sides of the proportion such as miles and hours, leaving us with the desired units of meters and seconds. Then calculate m/s by multiplying 45 by 1000 meters and then dividing that value by 3600 seconds.
The resulting answer is 45mph = 12.5 m/s
