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For each scenario, use the formula to find the standard error of the distribution of differences in sample means, \(\bar{x}_{1}-\bar{x}_{2}\) Samples of size 300 from Population 1 with mean 75 and standard deviation 18 and samples of size 500 from Population 2 with mean 83 and standard deviation 22

Short Answer

Expert verified
The standard error of the distribution of differences in sample means is approximately 3.59

Step by step solution

01

Identify the values

Identify the values from the problem: \(\sigma_{1} = 18\), \(n_{1} = 300\), \(\sigma_{2} = 22\), \(n_{2} = 500\)
02

Plug into the equation

Plug these values into the equation for the standard error of the distribution of differences in sample means: \(\sqrt{(18^{2}/300 + 22^{2}/500)}\)
03

Calculate

Preliminary calculation results in \(\sqrt{(3.24 + 9.68)}\)
04

Compute the square root

Finally, compute the square root: \(\sqrt{12.92}\)

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Most popular questions from this chapter

Using Data 5.1 on page \(375,\) we find a significant difference in the proportion of fruit flies surviving after 13 days between those eating organic potatoes and those eating conventional (not organic) potatoes. ask you to conduct a hypothesis test using additional data from this study. \(^{40}\) In every case, we are testing $$\begin{array}{ll}H_{0}: & p_{o}=p_{c} \\\H_{a}: & p_{o}>p_{c}\end{array}$$ where \(p_{o}\) and \(p_{c}\) represent the proportion of fruit flies alive at the end of the given time frame of those eating organic food and those eating conventional food, respectively. Also, in every case, we have \(n_{1}=n_{2}=500 .\) Show all remaining details in the test, using a \(5 \%\) significance level. Effect of Organic Bananas after 15 Days After 15 days, 345 of the 500 fruit flies eating organic bananas are still alive, while 320 of the 500 eating conventional bananas are still alive.

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