Converting Millimeters to Centimeters

Worked unit conversion example problem

A centimeter tape measure arranged in a spiral shape

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This example problem demonstrates how to convert millimeters to centimeters, which is actually much easier than you may have thought.

The Problem

Express 312 millimeters in centimeters.

In order to calculate this problem, you'll need to know how many millimeters make up a single centimeter. The following is the equation for centimeters to millimeters:

1 centimeter = 10 millimeters

From here, you can set up the conversion so the desired unit will be canceled out. In this case, we want cm to be the remaining unit.
distance in cm = (distance in mm) x (1 cm/10 cm)
distance in cm = (312/10) cm
distance in cm = 3.12 cm

The Answer

312 millimeters is 3.12 centimeters.