Question 1120191
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out of 7 consonants and 4 vowels, how many words each containing 3 consonants and 2 vowels can be formed?
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The condition says nothing about repeating/non-repeating letters. I will consider the case when <U>repeating is NOT allowed</U>.


<pre>
We can select 3 different consonants out of 7 by  {{{C[7]^3}}} ways;

We can select  2 different vowels out of 4  by  {{{C[4]^2}}} ways;

We can order  any 3+2 = 5 letters word by  5! = 120 ways.


So, the number of ways in this case is equal to   {{{C[7]^3}}}.{{{C[4]^2}}}.{{{120}}}.
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