How many ways are there to arrange the letters in the word Tennessee?
A. 1
B. 1260
C. 3780
D. 7560
E. 11340
OA C
Source: Veritas Prep
How many ways are there to arrange the letters in the word
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------------ASIDE-----------------BTGmoderatorDC wrote:How many ways are there to arrange the letters in the word Tennessee?
A. 1
B. 1260
C. 3780
D. 7560
E. 11340
OA C
Source: Veritas Prep
When we want to arrange a group of items in which some of the items are identical, we can use something called the MISSISSIPPI rule. It goes like this:
If there are n objects where A of them are alike, another B of them are alike, another C of them are alike, and so on, then the total number of possible arrangements = n!/[(A!)(B!)(C!)....]
So, for example, we can calculate the number of arrangements of the letters in MISSISSIPPI as follows:
There are 11 letters in total
There are 4 identical I's
There are 4 identical S's
There are 2 identical P's
So, the total number of possible arrangements = 11!/[(4!)(4!)(2!)]
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In TENNESSEE :
There are 9 letters in total
There are 4 identical E's
There are 2 identical N's
There are 2 identical S's
So, the total number of possible arrangements = 9!/[(4!)(2!)(2!)] = 3780
Answer: C
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Brent
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If the letters in Tennessee were all different, then we could arrange the letters in 9! ways. However, there are 4 occurrences of the letter e and 2 occurrences each of the letters n and s. We use the indistinguishable permutations formula, which requires that we divide by the factorial of each of the number of indistinguishable letters. Thus, the number of ways one can arrange the letters in Tennessee is:BTGmoderatorDC wrote:How many ways are there to arrange the letters in the word Tennessee?
A. 1
B. 1260
C. 3780
D. 7560
E. 11340
OA C
Source: Veritas Prep
9!/(4!2!2!) = 3780
Answer: C
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