How many different ways are there of arranging the letters

aniawnua

aniawnua

Answered question

2022-05-28

How many different ways are there of arranging the letters in the word BARBARIAN?

Answer & Explanation

zwichtsu

zwichtsu

Beginner2022-05-29Added 9 answers

Step 1
There are ( 9 2 ) ways to place the Bs.
From the remaining 7 spots, there are ( 7 3 ) ways to place the As.
From the remaining 4 spots, there are ( 4 2 ) ways to place the Rs.
In the remaining 2 spots, there are 2! ways to arrange the I and the N
Step 2
Thus the total possible arrangements is
( 9 2 ) ( 7 3 ) ( 4 2 ) 2 ! = 9 ! 7 ! 2 ! 7 ! 4 ! 3 ! 4 ! 2 ! 2 ! 2 ! = 9 ! 3 ! 2 ! 2 ! = 15120
Note that we could also write this as 9 ! 3 ! 2 ! 2 ! 1 ! 1 ! .
with the factorials in the denominator matching the "groups" of letters (3 As, 2 Bs, 2 Rs, 1 I, 1 N). Looking at how the cancellation worked when we did our initial multiplication, we can see how it will work out this way in general, and so as a shorthand, we can write this using the multinomial coeffficient
( 9 3 2 2 1 1 )

Do you have a similar question?

Recalculate according to your conditions!

New Questions in High school probability

Ask your question.
Get an expert answer.

Let our experts help you. Answer in as fast as 15 minutes.

Didn't find what you were looking for?