00:01
For this question, we are told that the number of misprints on a page of a certain paper will call that random variable x as a pluson distribution with a mean of 1 .2.
00:13
So that is mu is equal to 1 .2.
00:18
And for the first question, we are asked to find probability of two misprints on page.
00:26
So that is the probability that x equals 2.
00:30
Now for a plus on random variable, the probability mass function is given by this formula.
00:55
So this is equal to 1 .2 to the exponent 2 times e to the minus 1 .2 over 2 factorial.
01:08
And this comes out to 0 .2169.
01:16
Then for b we are asked for the probability of at least one misprint on two pages.
01:29
Now the mean was 1 .2, that was for one page.
01:34
So we have a second mean here, which is the mean for two pages.
01:39
That's going to be 2 times 1 .2.
01:40
1 .2 or 2 .4.
01:45
In some textbooks, instead of the mean being represented by mu, we have lambda times t...