Question

find the critical values for the following:

1. one-tail decreasing a= 0.03

2. one-tail decreasing, a= .025

3. two-tails, a=.015

Answer 1

we want to find the critical values for the following cases using standard normal z-table. Since sample size are not given we can't find other critical values,

1) one-tail decreasing a = 0.03,

Using standard normal z-table we get, z-score corresponding probability 0.03 is Z = -1.88

z-crtical value at a = 0.03 is , Zc = -1.88

2) one-tail decreasing, a = 0.025

Using standard normal z-table we get z-score corresponding probability 0.025 is Z = -1.96

z-critical value at a = 0.025 is Zc = -1.96

3) two-tails, a = 0.015

a/2 = 0.015/2 = 0.0075

Using standard normal z-table we get, z-score corresponding probability 0.0075 is, Z = -2.43

since it is two-tail, critical values are, -2.43 and 2.43

Zc = +/- 2.43