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Question
How many four digit different numbers, greater than 5000 can be formed with the digits 1, 2, 5, 9, 0 when repetition of digits is not allowed?
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Solution
As the number has to be greater than 5000, the first digit can either be 5 or 9.
Hence, it can be filled only in two ways.
Number of ways for filling the second digit = 4
Number of ways for filling the third digit = 3
(as repetition is not allowed)
Number of ways for filling the fourth digit = 2
Total numbers `2xx4xx3xx2=48`
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