Two separate marketing teams, Team A and Team B, have each designed a 30 second advertisement for the new Cloak soft drink. The manager of marketing is interested to see if there is any difference between the effectiveness of the two ads.

A random sample of 150 people are shown the ad from Team A and asked if they would definitely buy the new drink. In this sample, a proportion of 0.680 people said that they would (to 3 decimal places). A second random sample of 150 people are shown the ad from Team B and asked if they would definitely buy the drink. In this sample, a proportion of 0.280 people said that they would (to 3 decimal places).

Let₁denote the population proportion of people that would definitely buy the drink if they saw the ad from Team A. Let₂denote the population proportion of people that would definitely buy the drink if they saw the ad from Team B.

A hypothesis test is conducted with the following hypotheses:

H₀:₁=₂

H_A:₁₂

The level of significance used in this test is 0.05. You may find thisstandard normal tableuseful.

a)Calculate the test statistic (z) for this test. Give your answer to 2 decimal places.

z =

b)In this test the null hypothesis

is

is not

rejected.