Thread: Permutation of theory

Each permutation of the letters in THEORY is written on a slip of paper and tossed into a bowl. One slip is drawn at random, what is the probability that the letter T willappear in the last position?

Originally Posted by Jigglypuff

Each permutation of the letters in THEORY is written on a slip of paper and tossed into a bowl. One slip is drawn at random, what is the probability that the letter T willappear in the last position?

THEORY... Six letters.
Only one can come last at any given time.
There's a one in six chance that this will be 'T'.
So: 1/6.
That's probably the simplest way of looking at it...

You could also say that you had:
5/6 * 4/5 * 3/4 * 2/3 * 1/2 * 1/1 = 1/6.

I think...

Hello, Jigglypuff!

Yet another approach . . .

Each permutation of the letters in is written on a slip of paper
and tossed into a bowl. One slip is drawn at random.
What is the probability that the letter will appear in the last position?

There are permutations of the six letters.
. . Hence, there are 720 slips of paper in the bowl.


If is last: .
. . the other 5 letters can be arranged in ways.
Hence, there are 120 slips with in the last position.


Therefore: .