For a standard normal random variable z, find

Question

a) P[Z< .62]

b) P[Z < -.62]

C) P[Z> 1.59]

D) P[-1.3< Z< 2.61]

E) P[|Z| < 1.65]

Answer 1

You need to look these up in a Z table of standard Normal probabilities.  There should be one in your textbook or you can find one online.  I'll show you the answers for a few of these so you can check your work and give you a hint on the last one.    

 

a) P[Z<.62] = .7324

 

C) P[Z>1.59] = 1 - P[Z<1.59] = 1 - .9441 = .0559 

 

D) P[-1.3<Z<2.61] = P[Z<2.61] - P[Z<-1.3] = .9955 - .0968 = .8987

 

E) P[|Z|<1.65] = P[-1.65<Z<1.65]