Consider a number 235, where last digit is the sum of first two digits i.e. 2 + 3 = 5. How many such 3-digit numbers are there?

1+1 = 2
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2+1 = 3
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3+1 = 4
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3+2 4+1 = 5
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3+3 4+2 5+1 = 6
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3+4 4+3 5+2 6+1 = 7
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3+5 4+4 5+3 6+2 7+1 = 8
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3+6 4+5 5+4 6+3 7+2 8+1 = 9
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23 Combinations.
If you Reverse these sequence get another 22.

I Think the answer is 55. Doe anyone agree with me?