THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
A restaurant manager was in charge of purchasing new microwaves for his restaurant.The choices were narrowed to two available models.Since the two models cost about the same,the manager was interested in determining whether there was a difference in the amount of power consumed when operated at high voltages.Based on two independent random samples,the following summary information was computed:

-Find a 99% confidence interval for the difference in the amount of power consumed at high voltages by the two models.
A)0.2 ± 0.86
B)0.2 ± 0.58
C)0.2 ± 0.64
D)0.2 ± 0.77

Question

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
A restaurant manager was in charge of purchasing new microwaves for his restaurant.The choices were narrowed to two available models.Since the two models cost about the same,the manager was interested in determining whether there was a difference in the amount of power consumed when operated at high voltages.Based on two independent random samples,the following summary information was computed:
 
-Find a 99% confidence interval for the difference in the amount of power consumed at high voltages by the two models.
A)0.2 ± 0.86 
B)0.2 ± 0.58 
C)0.2 ± 0.64 
D)0.2 ± 0.77

Quizplus · Accepted Answer

The correct confidence interval is calculated using the formula for the confidence interval of the difference between two means. The margin of error is determined by the critical value for 99% confidence and the standard error of the difference. The choice D provides the correct margin of error for the given difference.