Question

In: Statistics and Probability

The scores on an examination in biology are approximately normally distributed with mean 500 and an...

The scores on an examination in biology are approximately normally distributed with mean 500 and an unknown standard deviation. The following is a random sample of scores from this examination.

406, 413, 441, 477, 530, 550

Find a

99%

confidence interval for the population standard deviation. Then complete the table below.

Carry your intermediate computations to at least three decimal places. Round your answers to at least two decimal places. (If necessary, consult a list of formulas.)

What is the lower limit of the

99%

confidence interval?
What is the upper limit of the

99%

confidence interval?

Solutions

Expert Solution

X:-  Score of examination in biology

Sr.No. X X-xbar (X-xbar)^2
1 406 -63.5 4032.25
2 413 -56.5 3192.25
3 441 -28.5 812.25
4 477 7.5 56.25
5 530 60.5 3660.25
6 550 80.5 6480.25
Total 2817 18233.5
xbar= Total / 6 469.5 S^2 = Total / 5 3646.7
S= square root(S^2) 60.39

df = n-1 = 6-1 = 5Lower limit = 32.99

Upper limit = 210.44


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