00:02
All right, this question asks us about a poisson distribution with an average of 48 calls per hour.
00:11
So part a asks, what is the probability of getting three calls in five minutes? so let's first compute the expected amount of calls in that time interval.
00:28
So there are 48 calls in 60 minutes, and we're dealing with five minutes.
00:43
And working that out, you'll see that the minutes that the minutes cancel, and we're left with four calls.
00:58
So now we can plug our expected value of four in for the mean and three in for observed.
01:07
So probability that x equals three equals four to the third power times e to the negative fourth all over three factorial.
01:23
And that is equal to 01954.
01:34
Alright, and then part b asks for 10 calls in 15 minutes.
01:47
So once again, we expect 48 calls in 60 minutes.
01:56
Times 15 minutes, minutes cancel, and in this case, we're left with 12 as our expected value.
02:11
So we want to find the probability that there are 10 calls in this interval, raised to the observed times e to the negative of our expected all over our observed factorial, and that works out to be 0 .1048...