To compare the effect of weather on sales of soft drinks, a soda manufacturer sampled two regions of the country with the following results. Is there a difference in sales between the 2 regions? i. The null hypothesis is p_a- p_b= 0. ii. The alternate hypothesis is p_a- p_b 0. iii. The z-statistic is 3.40. A) (i), (ii), and (iii) are all correct statements. B) (i) and (ii) are correct statements but not (iii). C) (i) and (iii) are correct statements but not (ii). D) (ii) and (iii) are correct statements but not (i). E) (ii) is a correct statement but not (i) and (iii).

Question

To compare the effect of weather on sales of soft drinks, a soda manufacturer sampled two regions of the country with the following results. Is there a difference in sales between the 2 regions? i. The null hypothesis is p_a- p_b= 0. ii. The alternate hypothesis is p_a- p_b> 0. iii. The z-statistic is 3.40. A) (i), (ii), and (iii) are all correct statements. B) (i) and (ii) are correct statements but not (iii). C) (i) and (iii) are correct statements but not (ii). D) (ii) and (iii) are correct statements but not (i). E) (ii) is a correct statement but not (i) and (iii).

Quizplus · Accepted Answer

The null hypothesis states that there is no difference in sales between the two regions. The alternate hypothesis states that there is a difference in sales, specifically that Region A has higher sales than Region B. The z-statistic measures the difference between the sample proportions of sales in the two regions and compares it to the expected difference under the null hypothesis. A z-statistic of 3.40 indicates a significant difference between the two regions, and we can reject the null hypothesis in favor of the alternate hypothesis. Therefore, (i) and (iii) are correct statements, but (ii) is not correct because the alternate hypothesis is testing for a one-sided difference, not a two-sided difference.

To Compare the Effect of Weather on Sales of Soft