Sometimes, you will see an equation that you can't solve just by using simple addition. Here's an example:

3
5
+
2
7

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Right To Left. We first see the 5, which is above the 7.  5 + 7 = 12. We put the 2 (from the 12) below the 7 and the 1 (from the 12) above the next column to the left.

Our equation is now:

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3
5
+
2
7

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Again we go from Right To Left and see the 1 above the 3.  1 + 3 = 4 and 4 + 2 = 6. Our equation is now:

3
5
+
2
7

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Here's another example:

8
4
5
+

3
2
9

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Right To Left. We first see the 5, which is above the 9.  5 + 9 = 14. We put the 4 (from the 14) below the 9 and the 1 (from the 14) above the next column to the left.

Our equation is now:

8
4
5
+

3
2
9

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Again we go from Right To Left and see the 1 above the 4.  1 + 4 = 5 and 5 + 2 = 7. Our equation is now:

8
4
5
+

3
2
9

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Once again we go from left to right. 8 + 3 = 11. Because there are no more columns, we just write the 11 below the 3:

8
4
5
+

3
2
9

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