Question

A manufacturer of potato chips would like to know whether its bag filling machine works correctly at the 410.0410.0 gram setting. Based on a 4646 bag sample where the mean is 412.0412.0 grams, is there sufficient evidence at the 0.10.1 level that the bags are overfilled? Assume the standard deviation is known to be 20.020.0.

Enter the Hyptheses

Enter the value of the z test statistic. Round your answer to two decimal places.

one tailed or two tailed?

Reject if H0 if z is greater than? Reject or Fail to reject?

Answer 1

a) As we are trying to test whether the bags are overfilled, therefore the null and alternate hypothesis here are given as:

b) The test statistic here is computed as:

Therefore 0.68 is the test statistic value here. ( rounded to 2 decimal places )

As we are only testing it from upper side, therefore this is a one tailed test.

For 0.1 level of significance, we get from the standard normal tables that:

P(Z > 1.282 ) = 0.1

Therefore we reject H₀ is Z > 1.282

As the test statistic here is less than 1.282, Therefore we fail to reject the null hypothesis here.