## Conversion formula

The conversion factor from feet per second to miles per hour is 0.68181818181818, which means that 1 foot per second is equal to 0.68181818181818 miles per hour:

1 ft/s = 0.68181818181818 mph

To convert 31.5 feet per second into miles per hour we have to multiply 31.5 by the conversion factor in order to get the velocity amount from feet per second to miles per hour. We can also form a simple proportion to calculate the result:

1 ft/s → 0.68181818181818 mph

31.5 ft/s → V(mph)

Solve the above proportion to obtain the velocity V in miles per hour:

V(mph) = 31.5 ft/s × 0.68181818181818 mph

V(mph) = 21.477272727273 mph

The final result is:

31.5 ft/s → 21.477272727273 mph

We conclude that 31.5 feet per second is equivalent to 21.477272727273 miles per hour:

31.5 feet per second = 21.477272727273 miles per hour

## Alternative conversion

We can also convert by utilizing the inverse value of the conversion factor. In this case 1 mile per hour is equal to 0.046560846560847 × 31.5 feet per second.

Another way is saying that 31.5 feet per second is equal to 1 ÷ 0.046560846560847 miles per hour.

## Approximate result

For practical purposes we can round our final result to an approximate numerical value. We can say that thirty-one point five feet per second is approximately twenty-one point four seven seven miles per hour:

31.5 ft/s ≅ 21.477 mph

An alternative is also that one mile per hour is approximately zero point zero four seven times thirty-one point five feet per second.

## Conversion table

### feet per second to miles per hour chart

For quick reference purposes, below is the conversion table you can use to convert from feet per second to miles per hour

feet per second (ft/s) miles per hour (mph)
32.5 feet per second 22.159 miles per hour
33.5 feet per second 22.841 miles per hour
34.5 feet per second 23.523 miles per hour
35.5 feet per second 24.205 miles per hour
36.5 feet per second 24.886 miles per hour
37.5 feet per second 25.568 miles per hour
38.5 feet per second 26.25 miles per hour
39.5 feet per second 26.932 miles per hour
40.5 feet per second 27.614 miles per hour
41.5 feet per second 28.295 miles per hour