Karen claims that the odds against randomly drawing the letter S from the letters in the word MISSISSIPPI are 4:7. How do you respond?

3 answers

The ratio is 4:7, but the odds are 4/11, # Ss vs the total possible choices.
prob of drawing an S = 4/11
prob of NOT drawing an S = 1 - 4/11 = 7/11

So the odds in favour of drawing an S
= (4/11) : (7/11)
= 4 : 7

So the odds AGAINST drawing an S = 3 : 7

I would say, "Karen, read the question carefully"
Argghhh!
the odds AGAINST drawing an S = 7 : 3