Question

Josh types the five entries in the bibliography of his term paper in random order , forgetting that thet should be in alphabetical oder by author ,What is the probability that he actually typed them in a alphabetical order?

Answer 1

First lets figure out how many different ways the guy can type the five entries.
When he types the first he has 5 things to choose from.
Then 4 for the second.
Then 3. Then 2. Then 1.
So 5*4*3*2*1 = 5! = 120
When he picks an order, it will be one out of those 120 possibilities, so the probability of him getting the correct order is
\[\frac{1}{120}\]

Answer 2

tk

Answer 3

1/120

Answer 4

How you get fraction?

Answer 5

5!=120
than how you get fraction
1/120 ?

Answer 6

because you wanted a probability. Probabilities are less than 1. The guy is only going to type one case out of the 120 so the probability is 1/120

Answer 7

ok, I see ty