Question

For a confidence level of 85%, find the critical value for a normally distributed variable. The sample mean is normally distributed if the population standard deviation is known.

Answer 1

The value is
`Z_(\alpha ) = 1.439`

Explanation:

From the question we are told that

The confidence level is C = 85%

Generally the level of significance is mathematically represented as

`\alpha = (100 - 85 )\%`

`\alpha = 0.15`

Now from the normal distribution table the critical value of
`\alpha` is

`Z_(\alpha ) = 1.439`