Question

A researcher wishes to see if the average number of sick days a worker takes per year is greater than 5. A random sample of 32 workers at a large department store had a mean of 5.6. Assume the population standard deviation is 1.2. Test the claim that the average number of sick days a worker takes per year is more than 5. Use a 0.01 significance level.

a)State the claim and opposite symbolically.

b) State the Null and alternate hypotheses symbolically.

c) Identify the significance level.

d) Find the P-value

e) State the decision

f) State the conclusion

Answer 1

Solution :

= 5

=5.2

=1.2

n = 32

This is the right tailed test .

The null and alternative hypothesis is ,

H0 :    = 5

Ha : >5

Test statistic = z

= ( - ) / / n

= (5.2-5) / 1.2 / 32

= 0.03

Test statistic = z = 0.03

P(z >0.03 ) = 1 - P(z < 0.03 ) = 1 - 0.5120

P-value =0.4880

= 0.01

P-value >

0.4880 > 0.01

Fail to reject the null hypothesis .

There is not sufficient evidence to suggest that