To answer this question, you first need to find all the unique sets of 4 numbers that add up to 6. These are: 0006. 0051. 0042. 0033. 0411. 0321. 0222. 3111. 2211. Now we need to
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There only 4 numbers allowed: 4,5,6, or 7. so, the probability for: thousands:4(4,5,6, or 7) hundreds:4(4,5,6, or 7) tens:4(4,5,6, or 7) ones:4(4,5,6, or 7) so, the total solutions
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The easy answer is 0000 thru 9999, which is 10,000 combinations. A way to calculate this is by N**x where N is the number of digits possible (here, 10 different digits are possible)
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There are a combination of 10,000
http://www.chacha.com/question/howmany4digitsc...
