Q. 265.0( 2 Votes )

How many 6-digit

Answer :

Given, numbers are 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9


The total number of these digits are 10


To find: 6-digit telephone numbers starting with 35 and no digit appears more than once


So, fix the position of first two digits as 3 and 5



Now, we need to fill these 4 remaining places


Remaining number of digits are 8 (0, 1, 2, 4, 6, 7, 8, 9)


Arrange these 8 numbers at 4 places.


Formula used:


Number of arrangements of n things taken r at a time = P(n, r)



The total number of ways


= the number of arrangements of 8 things taken 4 at a time


= P(8, 4)





= 8 × 7 × 6 × 5


= 1680


Hence, possible number of 6-digit telephone numbers starting with 35 are 1680


Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
caricature
view all courses
RELATED QUESTIONS :

Four letters E, KRD Sharma - Mathematics

. There are 6 iteRD Sharma - Mathematics

How many permutatRD Sharma - Mathematics

Find the total nuRD Sharma - Mathematics

In how many ways RD Sharma - Mathematics

From among the 36RD Sharma - Mathematics

How many differenRD Sharma - Mathematics

How many three-diRD Sharma - Mathematics

In how many ways RD Sharma - Mathematics

How many three-diRD Sharma - Mathematics