We have been learning different strategies to help us solve addition problems. Here are the strategies and how we could use them to solve an addition problem.

Doubles

8 + 8 = 16

Doubles Plus 1

5 + 6 = 5 + 5 = 10 and add 1 more which equals 11

Adding 10

45 + 10 = 55 (change the tens number but keep the ones the same!)

Counting On

Put the biggest number in our head and the smaller number on our hand and count on.

14 + 6

Put 14 in our head and then count on… 14 – 15, 16, 17, 18, 19, 20

Friends of 10

9 + 1 = 10

8 + 2 = 10

The 2 numbers always equal 10!

Adding 9

When you add 9 to a number, the ones number changes to the number before and the tens number changes to the next tens number. BUT when there is a 0 at the end of the number, the tens does NOT change.

37 + 9 = 46 (change both the tens and ones)

60 + 9 = 69 (change the ones but keep the tens the same)

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