How many 5-digit numbers are there in which three of the digits are 6, or two of the digits are 9 ?

The value  is  

Step-by-step explanation:

From the question we are told that

    The total  number of digit is  n = 5

     The total possible number of  6  is  k =  3

     The total possible number of  9  is  a = 2

Generally the number of way of representing a 5 digits number(i.e the number of five digit numbers ) in which 3 of the digit are 6 is mathematically represented as

Here P stands for permutation hence we are going to be making use of the permutation function in our calculators

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Generally the number of way of representing a 5 digits number(i.e the number of five digit numbers ) in which 2 of the digit are 9 is mathematically represented as

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Generally the number of 5-digit numbers there are in which three of the digits are 6, or two of  the digits are 9  is mathematically represented as

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