| 2 | Subtraction |
Just as addition is counting on, subtraction is counting away. We start with the total number, count away the number to be subtracted, and then see how many of the original items remain.
TAKING AWAY
Figure 2-1 shows an example of how subtraction works by counting away. When you were in grade school you might have said, “Eight take away three is five.” You would write this as 8 − 3 = 5. The teacher would say, “Three from eight is five.”
Figure 2-1
An example of subtraction as counting away with coins. Three from eight equals five. We write this as 8 − 3 = 5.
Many people, when first learning arithmetic, have more trouble with ...
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