- Uncle MichaelLv 71 month agoFavourite answer
Out of the 11 letters, there are 2 letters of 'B'.
P(B) = 2/11
Out of the 11 letters, there are 1 letter of 'P'.
P(P) = 1/11
Out of the 11 letters, there are 1 letter of 'A' and 2 letters of 'I".
P(A or I) = P(A) + P(I) = (1/11) + (2/11) = 3/11
P(not P) = 1 - P(P) = 1 - (1/11) = 10/11
- 1 month ago
There are ten letters in the word PROBABILITY. Some are repeated, B and I. The rest happen only once.
Imagine you have ten scrabble tiles with the ten letters on them, and you put them in a bag and shake them up and draw a tile without looking.