A population consists of 6 students were given the allotted time for studying and making tasks.
The number of hours are 2, 3, 4, 5, 6 and 7.
A. Find the mean and variance of the population. (10 points)
B. Using a sample size of 5, calculate the mean (𝜇𝑥̅) of the sampling distribution of the
sample means. Compare the result to the mean of the population.
Solution
A. Mean E(X)= (2+3+4+5+6+7)/6
=4.5
Variance= ∑[(X- E(X))2]/N
= 6.25+2.25+0.25+0.25+2.25+6.25/6
Var =2.9167
B. Sample sizes n=5
6C5=6
(2,3,4,5,6) (2,3,4,5,7) (3,4,2,6,7) (2,3,5,6,7) (2,4,5,6,7) (3,4,5,6,7)
E(x)= 4+4.2+4.4+4.6+4.8+5/6
=4.5
The sample and population mean are equal
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