Factor label method for unit conversions

Here's an approach that can increase your problem-solving skills, even if you're "math-challenged".                     
This method can guide you through problems where you are converting from one unit to another.  It has helped many students!

1.  Study the problem.  Write the known quantity with its units

          if unsure, choose a starting point that resembles the unknown.

2.  Multiply it by a fraction (the conversion factor)

          must be equal to one

          allows you to cancel unwanted units, and brings in new units if possible

3.  May have to repeat step 2 until all units cancel except the ones you need for the unknown

4.  Cancel the units, do the calculations.  Present the final answer with its units.


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