## Conversion formula

The conversion factor from feet per second to kilometers per hour is 1.0972799999991, which means that 1 foot per second is equal to 1.0972799999991 kilometers per hour:

1 ft/s = 1.0972799999991 km/h

To convert 3.9 feet per second into kilometers per hour we have to multiply 3.9 by the conversion factor in order to get the velocity amount from feet per second to kilometers per hour. We can also form a simple proportion to calculate the result:

1 ft/s → 1.0972799999991 km/h

3.9 ft/s → V(km/h)

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

V(km/h) = 3.9 ft/s × 1.0972799999991 km/h

V(km/h) = 4.2793919999966 km/h

The final result is:

3.9 ft/s → 4.2793919999966 km/h

We conclude that 3.9 feet per second is equivalent to 4.2793919999966 kilometers per hour:

3.9 feet per second = 4.2793919999966 kilometers per hour

## Alternative conversion

We can also convert by utilizing the inverse value of the conversion factor. In this case 1 kilometer per hour is equal to 0.23367805520055 × 3.9 feet per second.

Another way is saying that 3.9 feet per second is equal to 1 ÷ 0.23367805520055 kilometers per hour.

## Approximate result

For practical purposes we can round our final result to an approximate numerical value. We can say that three point nine feet per second is approximately four point two seven nine kilometers per hour:

3.9 ft/s ≅ 4.279 km/h

An alternative is also that one kilometer per hour is approximately zero point two three four times three point nine feet per second.

## Conversion table

### feet per second to kilometers per hour chart

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

feet per second (ft/s) kilometers per hour (km/h)
4.9 feet per second 5.377 kilometers per hour
5.9 feet per second 6.474 kilometers per hour
6.9 feet per second 7.571 kilometers per hour
7.9 feet per second 8.669 kilometers per hour
8.9 feet per second 9.766 kilometers per hour
9.9 feet per second 10.863 kilometers per hour
10.9 feet per second 11.96 kilometers per hour
11.9 feet per second 13.058 kilometers per hour
12.9 feet per second 14.155 kilometers per hour
13.9 feet per second 15.252 kilometers per hour