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If all possible numbers are formed by using the digits 1,2,3,5,7 without repetition and they are arranged in descending order, then the rank of the number 327 is 

Answer:

Explanation:

Number of possible 5 digit numbers is 120 

Number of possible 4 digit number is 120

 Number of possible  3 digit numbers start with 7 is 12

 Number of possible 3 digit numbers start with 5 is 12

 Then, according to order 3 digit numbers are 375,372,371,357, 352,351,327

 So , the rank of number  327 is 271