Short Cuts in Addition

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					Shortcuts in Addition
By Monica Yuskaitis

Adding Long Columns • Since addition is Commutative it doesn’t matter which numbers you add first.

4 + 2 + 5 + 1 = 12 1 + 4 + 5 + 2 = 12

Adding Long Columns

• Begin by looking for combinations
of ten.

34 57 83 + 26

Adding Long Columns

• Add up your ten combinations
first.
2

34 57 83 + 26
0

Adding Long Columns

• Add up your ten combinations
again.
2

34 57 83 + 26
200

Review Combinations of Ten

•1 + •8 + •2 + •4 + •9 +

9 2 8 6 1

= 10 = 10 = 10 = 10 =10

5+ 7+ 6+ 3+

5 3 4 7

= 10 = 10 = 10 = 10

Adding Long Columns

• When a number keeps repeating use
multiplication.
2

32 36 88 26 + 36

8

Adding Long Columns

• When a number keeps repeating use
multiplication.
2

32 36 88 26 + 36

218


				
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