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प्रश्न
How many different numbers of six digits can be formed from the digits 3, 1, 7, 0, 9, 5 when repetition of digits is not allowed?
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उत्तर
The first digit cannot be zero. Thus, the first digit can be filled in 5 ways.
Number of ways for filling the second digit = 5
(as repetition of digits is not allowed)
Number of ways for filling the third digit = 4
Number of ways for filling the fourth digit = 3
Number of ways for filling the fifth digit = 2
Number of ways for filling the sixth digit = 1
Total numbers = `5xx5xx4xx3xx2xx1= 600`
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