There are lots of "thinking tricks" you can use to make it easier to add numbers.
Use the ones that make sense to you!
Count From A Number Upwards
Example: 6 + 3
Think "6 ... 7, 8, 9"
Hint: start from the larger number
Example: 2 + 6
HARD
Start from 2 and count 6:
Think "2 ... 3, 4, 5, 6, 7, 8"
EASY
Start from 6 and count 2:
Think "6 ... 7, 8"
Do The Tens Last
Break big numbers into Tens and Units, add the Units, then add on the Tens.
Example: 14+5
Break the "14" into Tens and Units: 10 + 4
Add the Units: 4 + 5 = 9
Now add the Tens: 10 + 9 = 19
Think "4 plus 5 is 9, plus 10 is 19"
Another Example: 14 + 12
Break into Tens and Units: 10 + 4 + 10 + 2
Add the Units: 4 + 2 = 6
Now add on the Tens: 6 + 10 + 10 = 26
Aim for Ten
If you can see that a number is close to ten, then break the other number up so you reach ten.
Example: 9 + 7
9 is only 1 away from 10
so take 1 from the 7: 9 + 1 + 6
and give it to the 9: 10 + 6 = 16
Think "9 plus 1 is 10 ... 7 less 1 is 6, together is 16"
Another Example: 8 + 5
8+2=10, so lets take 2 from the 5: 8 + 2 + 3
and give it to the 8: 10 + 3 = 13
You can even move backwards to ten, by making the other number bigger as needed:
Example 12 + 7 = 12 - 2 + 9 = 10 + 9 = 19
Double when the numbers are the same
Example 5 + 5 = 2 x 5 = 10
Double if the numbers are close, then fix
Example: 5 + 6 is nearly two 5s, but 6 is 1 bigger than 5, so:
5 + 6 = two 5s + 1 = 10 + 1 = 11
Example: 7 + 9 is like two 8s, but 7 is 1 smaller than 8, and 9 is 1 bigger than 8 ... hey! it is exactly two 8s because 1 smaller and 1 bigger cancel each other:
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