Q18 of 140 Page 307

How many 7 - digit numbers can be formed by using the digits 1, 2, 0, 2, 4, 2, 4?

To find: number of 7 digit


0 can not be in the first place because that would make a 6 digit number


Total number of 7 - digit numbers = Total number of number possible - Number of numbers with 0 at the first place


Total number of numbers possible =


Number of numbers with 0 at first place =


Number of 7 - digit numbers = 420 - 60 = 360


360 seven - digit numbers are possible


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