A random sample of 30 students yielded a mean of x(bar) = 72 and a variance...
A random sample of 30 students yielded a mean of x(bar) = 72 and a variance of s2 = 10 for scores on a college placement test in mathematics. Assuming the scores to be normally distributed, construct a 95% confidence interval for σ2.
| a. |
[6.34 < σ2 < 18.07] |
|
| b. |
[7.38 < σ2 < 20.37] |
|
| c. |
[6.72 < σ2 < 19.36] |
|
| d. |
[7.61 < σ2 < 21.69] |
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A random sample of 30 students yielded a mean of x(bar) = 72 and
a variance...
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1. A random sample of 20 students yielded a mean ofT 72 and a variance of s2 16 for scores on a college placement test in mathematics. Assuming the scores to be normally distributed, construct a 98% confidence interval for σ2. Be sure to » State if the problem involves 1 population or 2 populations. If you have 2 populations, should they be paired or not? . State a State whether you should use z, t, or x2 and find...
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