Question

Find the p-value for the hypothesis test. A random sample of size 50 is taken. The sample has a mean of 420 and a standard deviation of 81.

H0: µ = 400

Ha: µ ≠ 400

The p-value for the hypothesis test is .

Your answer should be rounded to 4 decimal places.

Answer 1

this is the two tailed test .  

The null and alternative hypothesis is ,

H0 :   = 400

Ha :     400

Test statistic = z

= ( - ) / / n

= (420-400) / 81 / 50

= 1.75

P(z > 1.75) = 1 - P(z <1.75 ) = 1-0.9599=0.0401

P-value = 2*0.0401=0.0802