Pre Algebra Multiplicative Inverse
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One
Multiplicative Inverse

 
 Say we have one pizza that didn't get sliced.
 If we wanted to, we could write it as a fraction. 
 A very BORING fraction, 
 but still a fraction.
 

 
 If we had 2 of these unsliced pizzas could we add them together?
 Sure!
 

 
 So 5 of these pizzas that weren't sliced would be:
 

 
  So is this supposed to be a big deal or something?
 
 Well, not that big. But it does have some use here and there.
 Here is a way we can use it now.
 Say we have a 5. 
 What could we multiply it by to get 1?
 
 That is:
 

 Here's the answer:
 

 
 If you're into fancy math words you'll love this:

 

 
 Multiplicative Inverse just means the number 
 that you multiply something by to get 1.
 
 Example:
 
 What is the multiplicative Inverse of  12?
 

 
 Since:
 

 
 So if we have a fraction we can just flip it over 
 and THAT is the MULTIPLICATIVE INVERSE.
 
 And if we have a whole number, not a fraction, 
 we just write it OVER 1 and MAKE it a fraction.
 
 Example:
 
 What is the multiplicative inverse of :
 

 
 Flip it over and you get :

 
 And:

 

   copyright 2005 Bruce Kirkpatrick

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