Mrs. Bolvin's Easy Peasy Sure Fire Factor Label Method

1. Learn all the conversions necessary.  If you don't know them, memorize them.  The metric ones are easy if you know what the prefixes mean.  You will have great difficulty factor labeling in the metric system if you do not know the conversions.

2.  Start with what is given.  If the problem is in the form of a math equation (ex. 45 mm = ______________ hm, it’s the number written first.  If it is a word problem, it is the only number that isn’t matched up in an equation. (ex. If 25 books = 1 apple, how many apples are in 12.5 books?)

3. Don’t bother with the numbers, look at the units.  Whatever the units your first number has put that down below in the next blank.

4. Decide what you have to convert the unit you just wrote into.  If you don’t know the conversion to do it directly, change it into a unit you do know, then change that into the unit you are suppose to have (that’s called a two stepper).             

 5.  For each conversion, ask which unit is larger put a 1 next to it.  Ask yourself how many of the other unit are in the larger unit.  Fill in the other #.  Cancel units that divide out.  

       

6. Do the math.  Multiply across the top write the number down.  Multiply across the bottom write the number down, divide the two numbers.  That is your answer.  By the way, put the numerator of the fraction in your calculator first.

 45 x 1 x1= 45/1000 = 0.045 m /100 = .00045                   12.5 x 1 = 12.5/25= 0.5 apples