40 millimeters in centimeters

Result

The conversion result is: 40 millimeters is equivalent to 4 centimeters.^[1]

Conversion formula
How to convert 40 millimeters to centimeters?

We know (by definition) that: 1 mm = 0.1 cm.

We can set up a proportion to solve for the number of centimeters.

1 mm / 40 mm = 0.1 cm / x cm

Now, we cross multiply to solve for our unknown x:

x cm = (40 mm / 1 mm) * 0.1 cm → x cm = 4.0 cm

Conclusion:

40 mm = 4.0 cm

Conversion in the opposite direction

The inverse of the conversion factor is that 1 centimeter is equal to 0.25 times 40 millimeters.

It can also be expressed as: 40 millimeters is equal to 1 / 0.25 centimeters.

Approximation

An approximate numerical result would be: forty millimeters is about zero centimeters, or alternatively, a centimeter is about zero times forty millimeters.