Advertisement Remove all ads

How Many Three-digit Numbers Are There with No Digit Repeated? - Mathematics

Advertisement Remove all ads
Advertisement Remove all ads
Advertisement Remove all ads

How many three-digit numbers are there with no digit repeated?

Advertisement Remove all ads

Solution

The thousand's place cannot be zero.
∴ Number of ways of selecting the thousand's digit = 9
Number of ways of selecting the ten's digit = 9 ( as repetition of digits is not allowed and one digit has already been used in the thousand's place)
Similarly, number of ways of selecting the unit's digit = 8 (as two digits have been used for the thousand's and the ten's places)
∴ Total three digit number that can be formed = 9\[\times\]9\[\times\]8 = 648

Concept: Combination
  Is there an error in this question or solution?

APPEARS IN

RD Sharma Class 11 Mathematics Textbook
Chapter 16 Permutations
Exercise 16.2 | Q 16 | Page 15

Video TutorialsVIEW ALL [1]

Advertisement Remove all ads
Share
Notifications

View all notifications


      Forgot password?
View in app×