Question

Statistics/ Probability question- Please show me how to enter in to Excel to find values-thank you!

1. A) Assume that z-scores are normally distributed with a mean of 0 and a standard deviation of 1.
If P(z>c)=0.0868P(z>c)=0.0868, find c.

B) Assume that z-scores are normally distributed with a mean of 0 and a standard deviation of 1.
If P(z>d)=0.9935P(z>d)=0.9935, find d.

C) For the standard normal distribution, find the value of c such that:
P(z > c) = 0.3271

D) For a standard normal distribution, find cc if
P(z > c) = 0.1551

Answer 1

Part a)

P(z>c)=0.0868

P ( Z > c ) = 1 - 0.0868 = 0.9132

Looking for the probability 0.9132 in standard normal table to find the critical value Z

Z = 1.36

P ( Z > 1.36 ) = 0.0868

Excel formula NORMSINV( 0.9132 )

Part b)

P(z>d)=0.9935

P ( Z > d )= 1 - 0.9935 = 0.0065

Looking for the probability 0.0065 in standard normal table to find the critical value Z

Z = -2.48

P ( Z > -2.48 ) = 0.9935

Excel formula NORMSINV( 0.0065)

Part c)

P(z > c) = 0.3271

P(z > c) = 1 - 0.3271 = 0.6729

Looking for the probability 0.6729 in standard normal table to find the critical value Z

Z = 0.45

P ( Z > 0.45 ) = 0.9935

Excel formula NORMSINV( 0.6729 )

Part d)

P(z > c) = 0.1551

P(z > c) = 1 - 0.1551 = 0.8449

Looking for the probability 0.8449in standard normal table to find the critical value Z

Z = 1.01

P ( Z > 1.01 ) = 0.1551

Excel formula NORMSINV( 0.8449)