Astatistics instructor who teaches a lecture section of 160 students wants to determine whether students have more difficulty with one-tailed hypothesis tests or with two-tailed hypothesis tests. on the next exam, 80 of the students, chosen at random, get a version of the exam with a 10-point question that requires a one-tailed test. the other 80 students get a question that is identical except that it requires a two-tailed test. the one-tailed students average 7.81 points, and their standard deviation is 1.06 points. the two-tailed students average 7.64 points, and their standard deviation is 1.33 points.

There is no evidence that there is no significant difference between the sample means

Step-by-step explanation:

given that a  statistics instructor who teaches a lecture section of 160 students wants to determine whether students have more difficulty with one-tailed hypothesis tests or with two-tailed hypothesis tests. On the next exam, 80 of the students, chosen at random, get a version of the exam with a 10-point question that requires a one-tailed test. The other 80 students get a question that is identical except that it requires a two-tailed test. The one-tailed students average 7.81 points, and their standard deviation is 1.06 points

The two-tailed students average 7.64 points, and their standard deviation is 1.33 points.

Group   One tailed X     Two tailed Y  

Mean7.81007.6400

SD1.06001.3300

SEM0.11850.1487

N80      80  

(Two tailed test)

The mean of One tailed X minus Two tailed Y equals 0.1700

t = 0.8940

 df = 158

p value =0.3727

 p is greater than alpha 0.05

There is no evidence that there is no significant difference between the sample means

answer: b.48 for

step-by-step explanation:

about 0.75 hours

step-by-step explanation: