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Chapter 10: Q 34. (page 644)

In an experiment to learn whether substance M can help restore memory, the brains of 20rats were treated to damage their memories. First, the rats were trained to run a maze. After a day, 10rats (determined at random) were given substance M and 7of them succeeded in the maze. Only 2of the 10control rats were successful. The two-sample z test for the difference in the true proportions

a. gives z=2.25,P<0.02 .

b. gives z=2.60,P<0.005 .

c. gives z=2.25,P<0.04 but not<0.02

d. should not be used because the Random condition is violated.

e. should not be used because the Large Counts condition is violated.

Short Answer

Expert verified

Option (e) is correct.

Step by step solution

01

Given Information

It is given that Normal requirement requires that the number of failures in the number of successes in both samples are greater than 10 .

02

Explanation

In first sample, there are 7successes and 2successes in second sample. Normal condition is not satisfied.

It should not be used as normal condition is violated.

Option (e) is correct.

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Most popular questions from this chapter

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