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# Statistics Probability Question watch

1. Four letters are picked at random from the word THURSDAY. What is theprobability that there is at least one vowel among the letters?

(a)11/14(b)4/7(c)3/14(d)1/15

I'm just a bit confused about what to do.
I know the total number of possibilities is 8C4 =70 but I don't know where to go from there.
Help is appreciated, thanks in advance
2. (Original post by jamesthelam)
Four letters are picked at random from the word THURSDAY. What is theprobability that there is at least one vowel among the letters?

(a)11/14(b)4/7(c)3/14(d)1/15

I'm just a bit confused about what to do.
I know the total number of possibilities is 8C4 =70 but I don't know where to go from there.
Help is appreciated, thanks in advance
Let be the number of vowels picked.
.
Now consider the ways one can pick no vowels at all.
3. (Original post by joostan)
Let be the number of vowels picked.
.
Now consider the ways one can pick no vowels at all.
Thanks, now that I think about it, it's obvious
4. (Original post by jamesthelam)
Thanks, now that I think about it, it's obvious
It crops up fairly frequently -something to watch out for.

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