Everyday math methods

> Same Change Rule Subtraction Method  <

 

Same Change Subtraction Rule Method

This method is best used when dealing with
two-digit numbers.  

It is based on the recognition that a subtraction
problem is easier if the smaller number ends in
one or more zeros.  


Using this rule makes the problem more user
friendly by changing the second number in the
problem to a number with a zero in the ones
place. And change the first number by the same
amount.

Example: 225 - 58 may be changed into 227 - 60

same change rule

225 + 2 = 227

58 + 2 = 60

 
 

Example: Same Change Subtraction

same change subtraction rule