Answer:
20160
Explanation:
Let's write the word PROBABLY. There are 8 letters in total, but the letter B repeats twice. So, instead of just doing 8! or 1*2*3*4*5*6*7*8, you have to exclude the two B's.
So, you have to do 8! / 2! because the 2! is the two B's.
Hope this helps!! :)