Question 933316
Help! How to find out all the possible outcomes 
for a sum of four numbers(0-9) = 20 ?
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There is no magic method.  You have to work it out.
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Start with 9
9+9+1+1
9+8+2+1
9+7+3+1
9+7+2+2
etc.
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Cheers,
Stan H.