There are 720 combinations if you use each of the digits only once per combination.
There are only 999 three digit whole numbers.
102 = 100 which is the first possible three digit number that is a perfect square. 312 = 961 which is the last possible three digit number that is a perfect square. So there are 22 three digit positive numbers that are perfect squares.
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There are 24 combinations if you use each digit only once per combination: 123 124 132 134 142 143 213 214 231 234 241 243 312 314 321 324 341 342 412 413 421 423 431 and 432.
3! or 6 combinations can be made from three distinct numbers. For this example they are: 345, 354, 534, 543, 435, 453.
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The answer will depend on how many digits there are in each of the 30 numbers. If the 30 numbers are all 6-digit numbers then the answer is NONE! If the 30 numbers are the first 30 counting numbers then there are 126 combinations of five 1-digit numbers, 1764 combinations of three 1-digit numbers and one 2-digit number, and 1710 combinations of one 1-digit number and two 2-digit numbers. That makes a total of 3600 5-digit combinations.
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NOT AN ANSWER:More acceptable combinations:1231 3213 2321More unacceptable combinations:1112 2222 3113Thanks.
6 ways: 931,913,139,193,391,319
If the numbers can be repeated and the numbers are 0-9 then there are 1000 different combinations.
There are 28706 such combinations. 5456 of these comprise three 2-digit numbers, 19008 comprise two 2-digit numbers and two 1-digit numbers, 4158 comprise one 2-digit number and four 1-digit numbers and 84 comprise six 1-digit numbers.
Only three: 12, 13 and 23. Remember that the combinations 12 and 21 are the same.
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999
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