If a z is a standard normal variable, find the probability that z is > -1.82. b. p(-0.73<z<2.27)

Question

If a z is a standard normal variable, find the probabilities (write your answer as a four place rounded decimal). the probability that z is > -1.82.  b.  p(-0.73<z<2.27)  c.  p(z<2.01)

Answer 1

Using the z table here ( http://www.stat.ufl.edu/~athienit/Tables/Ztable.pdf ):

p(z<-1.82) = 0.0344

p(z>=1.82) = 1 - 0.0344 = 0.9656

.

p(-0.73<z<2.27)

p(z<2.27) - p(z<-0.73)

1 - p(z>2.27) - p(z<-0.73)

1 - p(z<-2.27) - p(z<-0.73)

1 - 0.0116 - 0.2327

1 - 0.2443

0.7557

.

p(z<2.01)

1 - p(z>2.01)

1 - p(z<-2.01)

1 - 0.0222

0.9778