Question

Question
How many distinct rearrangements of the letters in 'QLBLQBLBB' are there?
Select the correct answer below:
O 1638
O 4200
O 882
O 420
O 1260

Answer 1

Answer:

D

Step-by-step explanation:

There are 9 letters, which contains 2Qs, 3Ls and 4Bs.

If the 9 letters are distinct, the number of permutations they have will be 9!.

! is the factorial sign.

9! = 9*8*7*6*5*4*3*2*1

HOWEVER, we have some identical elements, so we need to get rid of the permutations of the same letters.

Thus we have:

$\dfrac{9!}{2!*3!*4!} =\dfrac{9*8*7*6*5}{2*3*2*1} = \dfrac{9*4*7*5}{1} = 63*20=1260$

The answer is D