Given the following computer printout for a set of sample data, which one of the following represents the value of the Interquar
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Answer:
We need a sample size of at least 75.
Step-by-step explanation:
We have that to find our level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of .
So it is z with a pvalue of , so
Now, we find the margin of error M as such
In which is the standard deviation of the population and n is the size of the sample.
The standard deviation is the square root of the variance. So:
With a .95 probability, the sample size that needs to be taken if the desired margin of error is 5 or less is
We need a sample size of at least n, in which n is found when M = 5. So
We need a sample size of at least 75.
If you notice the picture below
the composite figure is just a trapezoid sitting on top of a rectangle
and then, the rectangle has a triangular hole in it
so.. get the area of the trapezoid
then get the area of the rectangle, which is just a 12x14
and then get the area of the triangle, which surely you know is 1/2 bh
then, subtract the triangle's area from the rectangle's area
and whatever is left, namely the difference, add that to the area of the trapezoid, and that's the composite's area
namely the area of the trapezoid plus the rectangle's, minus the triangle's
the composite figure is just a trapezoid sitting on top of a rectangle
and then, the rectangle has a triangular hole in it
so.. get the area of the trapezoid
then get the area of the rectangle, which is just a 12x14
and then get the area of the triangle, which surely you know is 1/2 bh
then, subtract the triangle's area from the rectangle's area
and whatever is left, namely the difference, add that to the area of the trapezoid, and that's the composite's area
namely the area of the trapezoid plus the rectangle's, minus the triangle's