(h) How many 4-letter words can be spelled with 'a', 'b', 'c','d'? How many 4-letter words can be spelled using 'x', 'x', 'x', 'y'? Explain the relationship between your two answers.
I different solution: From the problem we can take the given data 0.4 letter words with a,b,c,d 34 different letters can be arranged to form a word in 4! ways = 4*3 x 2 x ways: 24 ways :: 4 letter words with X, X,X,Y Here we have 3 Same letters and letter, so no of words that can be formed 4!/3!11!)= 4!/3! 473X2X1 = 4 ways a word with repeating letters we will take the factorial of the number of times the letter is repeating 3 X2 X 1 » So, for forming M