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 Hi, Please help me out with this question! Consider the population of the first seven integers: 1, 2, 3, 4, 5, 6, and 7; N=7. For this population, mean = 2 and standard deviation = 2. a. How many samples of size three can be extracted from this population (sampling without replacement)? b. Form the complete set of samples of size three and for each sample, compute the sample mean and median. Thank you, Liz

Hi Liz,

You need to check your calculations again. The mean of the population is 4 not 2.

For part a the number of samples of size 3 is the number of ways of choosing 3 things from 7 things, sometimes called 7 choose 3 and written 7C3. Do you know how to calculate this?

For b part you need to list all the samples you counted in part a. Do so in an orderly way. I would start

{1, 2, 3}, {1, 2, 4}, {1, 2, 5}, { 1, 2, 6}, {1, 2, 7},
{1, 3, 4}, {1, 3, 5}, {1, 3, 6}, {1, 3, 7},
...
{1, 6, 7},
{2, 3, 4}, {2, 3, 5}, {2, 3, 6}, {2, 3, 7},
...

For each sample in the list find the mean and median.

I hope this helps,
Penny

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