find total number of odd interger between 1000 and 8000 have distinct digit ?

Dear Student

M= Number of number of 4 digited that  have distinct digits= 10P4=10X9X8X7------------------(1)

Number of 4 digited that  have distinct digits and starts/ends with a given digit= 9P3=9X8X7------(2)

the number of  integers starts with 0 or  8 or  9 in M= 3/10 of M=3X9X8X7----(4)

Number of number of 4 digited and inbetween 1000,8000 that  have distinct digits=(10X9X8X7)-(3X9X8X7)=7X9X8X7----(5)

And half of (5) are even 
==>total number of odd interger between 1000 and 8000 have distinct digit =(1/2)X7X9X8X7=1764

Regards

Team

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