 Hi, and welcome to the session. Let us discuss the following question that question says in how many of the distinct permutations of the letters N Mississippi To the four eyes not come together Before solving this question, you should first reverse with theorem 4 given in your NCRT book theorem 4 states that the number of permutations of N objects of even objects are of one kind two are of second kind so on pk are of k kind pictorial into p to pictorial so on pk pictorial The knowledge of this theorem is the key idea in this question Let's now begin with the solution In this question, we have to find number of permutations of the letters and Mississippi where the four eyes not come together now the letters of Mississippi are in the word Mississippi Out of these 11 letters appears 4 times so appears 4 times P appears 2 times and the rest are all different but you're a 4 which we have learned in key idea number of permutations of 11 different letters equal to 11 factorial upon 4 factorial into 4 factorial into 2 factorial Now these permutations Include those words come together and we will find permutations for words where four eyes come together and then we will subtract This number of permutations from total number of Permutations that is number of permutation of 11 different letters So let's now first find the number of permutations for words where four eyes come together Now what we will do we will take four eyes as As one unit that is I I I Now this unit Fills one place seven letters Fill the remaining seven places. So now We will have eight letters I Plus seven letters appears four times and P appears two times are all different theorem for number of Permutations Treated as one unit is equal to 8 factorial upon 4 factorial into 2 factorial Subtract number of permutation when four eyes are treated as one unit from the total number of permutations So required number of permutations is equal to factorial upon 4 factorial into 4 factorial into 2 factorial Minus 8 factorial upon 4 factorial into 2 factorial Now this is equal to 11 into 10 into 9 into 8 into 7 into 6 into 5 into 4 factorial upon 4 factorial into 4 into 3 into 2 into 1 into 2 into 1 Minus 8 into 7 into 6 into 5 into 4 Now this is equal to 11 into 10 into 9 into 7 into 5 minus 4 into 7 into 6 into 5 and this is equal to 34650 minus 840 and this is equal to 33810. Hence our required answer is 33810. This completes the session. Bye and take care.