Arithmetic Grade Five

Lesson One Hundred and Five: Cross Reducing Two

You can reduce the fractions that you are multiplying before you multiply them. Here's an example: 


	 2	   3	
	---   *   ---  =
         4         6

	Since 2/4 equals 1/2 and since 3/6 also equals 1/2,
	we can rewrite this problem like this:

	 1 	  1	  1
	---   *  ---  =  ---
	 2 	  2	  4
Here's another example: 

	 3	 4
	---  *  ---  =
	 9	 8

	Since 3/9 equals 1/3 and 4/8 equals 1/2, we
	can rewrite this problem like this:

	 1	 1	 1
	---  *  ---  =  ---
	 3	 2	 6

Now you get to try a few for yourself.

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