Q. What is the total number of different 9-letter arrangements that can be formed using the letters in the word AMENDMENT?Answer:
Count Letters and Frequencies: Determine the total number of letters and the frequency of each letter in the word AMENDMENT.The word AMENDMENT has 9 letters in total. The letter frequencies are as follows:A - 1 timeM - 2 timesE - 2 timesN - 2 timesD - 1 timeT - 1 time
Use Permutations Formula: Use the formula for permutations of a multiset to calculate the number of different arrangements.The formula is:Number of arrangements = n1!×n2!×…×nk!n!where n is the total number of letters, and n1,n2,…,nk are the frequencies of each distinct letter.For AMENDMENT, this becomes:Number of arrangements = 1!×2!×2!×2!×1!×1!9!
Calculate Total Factorial: Calculate the factorial of the total number of letters, which is 9!.9!=9×8×7×6×5×4×3×2×1=362,880
Calculate Letter Factorials: Calculate the factorial for each of the letter frequencies.Since the frequencies are 1 or 2, we only need to calculate 2!.2!=2×1=21!=1 (but we don't really need to calculate this since the factorial of 1 is 1)
Divide Factorials for Arrangements: Divide the total factorial by the product of the factorials of the letter frequencies.Number of arrangements = 1×2×2×2×1×1362,880Number of arrangements = 8362,880Number of arrangements = 45,360
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