﻿ The number of five digit telephone numbers having at least one of their digits repeated is : Kaysons Education

# The Number Of Five Digit Telephone Numbers Having At Least One Of Their Digits Repeated Is

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## Question

### Solution

Correct option is

69760

The number of five digit telephone numbers which can formed using the digits 0, 1, 2, … 9 is 105 (see example 19). The number of five digit telephone numbers which have none of their digits repeated is 10P5 = 30240. Thus, the required number of telephone numbers is 105 – 30240 = 69760.

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