Answer:
8.48528137424
Step-by-step explanation:
Answer:


Step-by-step explanation:
Given
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See attachment for grid
Solving (a): The coordinates of K
The parallelogram has the following diagonals: IJ and HK
Diagonals bisect one another. So:
Midpoint of IJ = Midpoint of HK
This gives:




Multiply through by 2

By comparison:


Solve for x and y


So, the coordinates of k is:

The length of JK is calculated using distance (d) formula

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So:





Hence:

Answer:
Where
and
We select a sample of n=16 and we are interested on the distribution of
, since the distribution for X is normal then we can conclude that the distribution for
is also normal and given by:

Because by definition:



And for this case we have this:


Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the IQ scores of a population, and for this case we know the distribution for X is given by:
Where
and
We select a sample of n=16 and we are interested on the distribution of
, since the distribution for X is normal then we can conclude that the distribution for
is also normal and given by:

Because by definition:



And for this case we have this:


Answer:
12
Step-by-step explanation:12x9