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Use these strategies when adding and subtracting two addends that are one apart.

            Doubles + 1 Strategy

                                                                  7+6 = ?

Take the smallest addend which is 6 and double it -->6 + 6 = 12

Then add one more --> 6 + 6 + 1 = 13

Doubles + 1 Song

What is 5 + 6? It's a Double + "1"... That's the trick!
5 + 5 is 10... Can you figure it out once again?
Now all you do is add "1";
Can you tell me now... the sum?

5 + 6 =

What is 6 + 7? It's a Double + "1"... That's math heaven!
6 + 6 is 12... Can you figure it out like my friend Melv?
Now all you do is add "1";
Can you tell me now... the sum?

6 + 7 =

What is 7 + 8? It's a Double + "1"... That makes it great!
7 + 7 is 14... Can you figure out just what I mean?
Now all you do is add "1";
Can you tell me now... the sum?

7 + 8 =

What is 8 + 9? It's a Double + "1"... That makes it fine!
8 + 8 is 16... Can you figure out just what I mean?
Now all you do is add "1";
Can you tell me now... the sum?

8 + 9 =

Doubles - 1

Doubles minus 1 is very similar, except you take the larger addend and double it.  Then, you subtract one.

                                            7 - 6 = ?

Take the largest addend which is 7 and double 7 + 7 = 14

Then subtract one --> 7 + 7 - 1 = 13