Dimensional analysis
While calculating one needs to convent units from one system to other. The method used to accomplish this is called factor label method or unit factor method or dimensional analysis.
Ex : 1 inch = 2.54 cm
\(\frac{1\, inch}{ 2.54 \,cm} = 1 = \frac{ 2.54\, cm }{1 \,inch}=1\)
Both these are called unit factors
