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adelina 88 [10]
3 years ago
15

The one‑sample t t statistic from a sample of n = 23 n=23 observations for the two‑sided test of H 0 : μ = 15 H0:μ=15 versus H α

: μ > 15 Hα:μ>15 has the value t = 2.24 t=2.24 . If the standard deviation from the sample is 2.4, what is the mean of these n = 23 n=23 observations?
Mathematics
1 answer:
givi [52]3 years ago
5 0

Answer:

Mean of these n = 23 observations is 16.21 .

Step-by-step explanation:

We are given with the one‑sample t statistic from a sample of n = 23 observations for the two‑sided test of H0 : μ = 15 versus Hα : μ > 15 has the value t = 2.24 . Also, the standard deviation from the sample is 2.4.

So, Null Hypothesis, H_0 : \mu = 15

Alternate Hypothesis, H_1 : \mu > 15

The test statistics that is used here is One sample t-test statistics;

             T.S. = \frac{\bar X-\mu}{\frac{s}{\sqrt{n} } } ~ t_n_-_1

where, \bar X = sample mean

            \mu = population mean = 15

            s = sample standard deviation = 2.4

            n = sample size = 23

So, test statistics = \frac{\bar X-15}{\frac{2.4}{\sqrt{23} } } ~ t_2_2

                  2.24  =  \frac{\bar X-15}{\frac{2.4}{\sqrt{23} } }

              2.24 \times {\frac{2.4}{\sqrt{23} } } = \bar X - 15  

              1.21 = \bar X - 15

                 \bar X = 1.21 + 15 = 16.21      

Therefore, mean of n = 23 observations is 16.21 .                  

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Step-by-step explanation:

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To study the threshold of hering the researcher took a random sample of 80 male college freshmen.

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8 0
3 years ago
Suppose a bag contains many marbles, 54% of which are purple. You draw 5 marbles from the bag with replacement.
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x = 2 = number of purple we want to get

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The \frac{n!}{x!(n-x)!} portion is from the nCr combination formula. The exclamation marks indicate a factorial.

Alternatively, you could use Pascal's Triangle for that portion.

<h3>Answer: 0.283831776</h3>

This decimal value is exact. Round it however you need to.

============================================================

Part B

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