Question

# While testing a claim about population mean, if the value of the population standard deviation σ...

While testing a claim about population mean, if the value of the population standard deviation σ is not known, then the distribution we use:CHOOSE

Binomial Distribution
Standard Normal Distribution
None
Student's t-Distribution

With H0: p = 0.4, Ha: p < 0.4 , the test statistic is z = – 1.68. Using a 0.05 significance level, the P-value and the conclusion about null hypothesis are:

0.0465; reject H0

0.093; fail to reject H0

0.9535; fail to reject H0

0.0465; fail to reject H0

1) While testing a claim about the population mean, if the value of the population standard deviation σ is not known, then we choose Student's t-Distribution

2) Here we are testing

H0: p = 0.4

vs

Ha: p < 0.4

So this is one-tail Z test

So p-value will be area to the left side of the test statistic in the standard normal distribution table

Here

z = – 1.68

So

p-value = 0.0465

And the level of significance is 0.05

As p-value is less than the level of significance we reject H0