Question

How many distinguishable permutations are there of the letters in BUBBLE?

Answer 1

There are 6 letters, hence 6! = 720 total permutations of BUBBLE. But there are 3 indistinguishable copies of B, so we divide by the number of ways we can rearrange them, 3! = 6. Then there are

6!/3! = 720/6 = 120

distinguishable permutations of BUBBLE.