Assume that the sample is a simple random sample obtained fr
Assume that the sample is a simple random sample obtained from a normally distributed population of IQ scores of statistics professors. Use the table below to find the minimum sample size needed to be 99% confident that the sample standard deviation s is within 50% of . Is this sample size practical?
To be 95% confident that s is within
1%
5%
10%
20%
30%
40%
50%
19,205
768
192
48
21
12
8
To be 99% confident that s is within
1%
5%
10%
20%
30%
40%
50%
33,218
1,336
336
85
38
22
14
The minimum sample size needed is
nothing.
Is this sample size practical?
A. No,because the sample size is excessively large to be practical for most applications.the sample size is excessively large to be practical for most applications.
B. Yes, because the sample size should be as large as possible for most applications.
C.Yes,because the sample size is small enough to be practical for most applications.the sample size is small enough to be practical for most applications.
D.No, because the sample size shoud be as small as possible for most applications.
| To be 95% confident that s is within | 1% | 5% | 10% | 20% | 30% | 40% | 50% | |
| of the value of , the sample size n should be at least | 19,205 | 768 | 192 | 48 | 21 | 12 | 8 | |
| To be 99% confident that s is within | 1% | 5% | 10% | 20% | 30% | 40% | 50% | |
| of the value of , the sample size n should be at least | 33,218 | 1,336 | 336 | 85 | 38 | 22 | 14 |
Solution

