Permutations and Combinations
How many numbers can be made with the digits lying between and , which are divisible by while repetition of any digit is not allowed in any number?
Correct Answer: Option(b)
Solution: The 4-digit number formed using the digits and is divisible by , hence it should end in . Therefore the unit place digit is always ,
Since the number lie between and , the thousands place digit has to be ,
Now, the middle 2 digits van be chose from the remaining 4 digits (namely and ) in ways.