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4 years ago

14

For males the expected pulse rate is 70 per second and the standard deviation is 10 per second. For women the expected pulse rat

e is 77 per second and the standard deviation is 12 per second. Let !X ¼ the sample average pulse rate for a random sample of 40 men and let !Y ¼ the sample average pulse rate for a random sample of 36 women.What is the approximate distribution of \overline{X}-\overline{Y} ? Justify your answer.

1 answer:

11Alexandr11 [23.1K]4 years ago

5 0

Answer:

Normal

Step-by-step explanation:

Given are the pulse rates average and std deviation for men and women.

Men Women Difference

Pulse rate per second 70 77 -7

Std dev per second 10 12

Variance 100 144 244

n 40 36

Variance/n 2.5 4 6.5

Std error 2.549509757

The first one represents X that of men and ii one that of women Y.

$\bar X -\bar Y$ is Normal

Mean = difference in means

and Std dev of difference = $\sqrt{\frac{\sigma_1^2 }{n_1} +\frac{\sigma_2^2 }{n_2}}$

Thus using the above we calculate the distribution of difference of means is Normal with mean = -7 and std error = 2.5495

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