Question

5. A)  The parameters of shape, bias (α3) and kurtosis (α4) for a normal distribution must take the values:

B) If X is a random variable with normal distribution with mean 2 and variance 9, and Z is a variable standard normal random, then P (0<x<4) is equal to:

C) A phone call came to a switch at a random time within a minute. The switch he was fully occupied for 15 seconds of that one minute period. The probability that the call will come when the switch is not busy is

Answer 1

5

A) The shape of the normal distribution is bell shapped or symmetric shape

In normal distribution, α3 = 0 i.e. coefficient of skewness is zero i.e. the distribution is symmetric

and α4 = 0 i.e. coefficient of kurtosis is zero i.e. mesokurtisis distribution or normal

B) If X is a random variable with normal distribution with mean 2 and variance 9, and Z is a variable standard normal random, then P (0<x<4) is equal to:

i.e.

c)

A telephone call arrives at a switchboard at random within a 1 minute interval. It is known that switchboard is fully busy for the first 15 seconds

One minute of time is (0,60) seconds