Thread: Permutations Questions

How many four-digit even #s can be formed if no digit is repeated?

9x9x8x4=2592 ?

Find the # of seven-digit telephone #s that can be generated if both of the following conditions are met:

CONDITION 1: The first digit cannot be 0 or 1.

CONDITION 2: The first three digits cannot be the emergency # (911) or the # used for information (411).

Originally Posted by cityismine

How many four-digit even #s can be formed if no digit is repeated?

There are two case.
1) If the number ends in 0: (9)(8)(7)
2) If the numberdoes not end in 0: (4)(9)(8)(7)