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How many 4 digit number are there with no digit reapeted |
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Answer» 9×9×8×7 is right ans For thousand\'s place we have 10 choices For hundred \'s place we have 9choices For ten\'s place we have 8choices For unit\'s place we have 7 choices => No. of 4 digit no. = 10×9×8×7 = 5040 For unit\'s place we have 10 choices , For ten\'s place we have 9 choices , For hundred\'s place we have 8 choi 4×4×4×4=256 |
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