JusTLucK04
How many different anagrams can you make for the word MATHEMATICS?
I donot have any options...but the correct answer here is 8!/2!
I don't understand how?
Should it not be 11!/(2!*2!*2!)
Your solution is correct. The correct answer is indeed 11!/(2!*2!*2!): the number of arrangement of 11 letters out of which 2 A's, 2 M's and 2 T's are the same.
Similar but much harder question to practice:
how-many-words-can-be-formed-by-taking-4-letters-at-a-time-92675.htmlTHEORY:
Permutations of \(n\) things of which \(P_1\) are alike of one kind, \(P_2\) are alike of second kind, \(P_3\) are alike of third kind ... \(P_r\) are alike of \(r_{th}\) kind such that: \(P_1+P_2+P_3+..+P_r=n\) is:
\(\frac{n!}{P_1!*P_2!*P_3!*...*P_r!}\).
For example number of permutation of the letters of the word "gmatclub" is 8! as there are 8 DISTINCT letters in this word.
Number of permutation of the letters of the word "google" is \(\frac{6!}{2!2!}\), as there are 6 letters out of which "g" and "o" are represented twice.
Number of permutation of 9 balls out of which 4 are red, 3 green and 2 blue, would be \(\frac{9!}{4!3!2!}\).
Hope this helps.