We have training courses which cover this and other topics in detail, but I’ll cover the basics here. When multiplying and dividing numbers with units, the units are either combined or are cancelled out.

When units are multiplied by each other, they are considered combined’, resulting in a completely new unit of measurement. When division is used between two different units, then the units are also combined to form the result. When like units are divided they cancel out.

When adding and subtracting numbers with units, it is important to ensure that all

the units are the same. If the units are different, they must first be converted for the result

to be useful. When added or subtracted, the units will remain unchanged when the result is calculated.