How many 3-digit numbers can be formed by using the digits 1 to 9 if n – InterviewSolution

InterviewSolution

1.	How many 3-digit numbers can be formed by using the digits 1 to 9 if no digit is repeated?
Answer» No. of ways of filling first place = 9<br> No. of ways of filling second place = 8<br> No. of ways of fillin third place = 7<br> Therefore, total numbers `= 89 xx 8 xx 7 504`.

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