- = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9 ( )
% < > + - = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9
( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8
9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7
8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6
7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5
6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3
106
Most of us fi nd addition easier than subtraction. We will learn in
this chapter how to make addition even easier.
Some numbers are easy to add. It is easy to add numbers like 1 and
2, 10 and 20, 100 and 200, 1,000 and 2,000.
Twenty-fi ve plus 1 is 26.
Twenty-fi ve plus 10 is 35.
Twenty-fi ve plus 100 is 125.
Twenty-fi ve plus 200 is 225.
Th ese are obviously easy, but how about adding 90? Th e easy way to
add 90 is to add 100 and subtract 10.
Forty-six plus 90 equals 146 minus 10. What is 146 minus 10? Th e
answer is 136.
46 + 90 = 146 – 10 = 136
A ADDITIONDDITION
CChapter 11hapter 11
- = x 0 1 2 3 4 5 6 7 8 9 ( ) % < > + - = x 0 1 2 3 4 5 6 7 8 9 ( )
brent
(Brent)
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