Permutations And Combinations Question 280
Question: The number of 5 digit telephone numbers having at least one of their digits repeated is [Pb. CET 2000]
Options:
A) 90,000
B) 100,000
C) 30,240
D) 69,760
Correct Answer: D
Show Answer
Answer:
Solution:
$ \therefore $ The required number of telephone numbers = $ 5\times 4=20 $ .
BETA
