Question
How many numbers lie between 2000 and 3000 divisible by
5 can be made with the digits 2, 3, 4, 5, 6, 7 and 8 without repeating any digit?Solution
Divisible of 5 means unit place must have 5 (since 0 is not in the list). And thousands place will always be 2. This leaves us with 5 digits (3, 4, 6, 7, 8) to be filled in 2 places (2 _ _ 5). This can be done in 5P2 ways or 20 ways. So 20 numbers can be formed.
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