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How many 4 digit number are there with no digit repeated |
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Answer» no. 0 to 9 total numbers= 10 1000th place can\'t be filled by 0 bcoz if 0 is used then it will become 3 digit number so 1000th place can only be filled by 1 to 9No. Of ways of filling 1000th place= 9No. Of ways of filling unit,10th & 100th place= 9×8×7Required 4 digit number = 9×9×8×7= 4536 =4536 9×9×8×7 There are such 9 numbers 9*8*7*10 |
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