Answer:
We need a sample size of at least 101
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, 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.
What sample size is needed to estimate the true average speed to within 2 mph at 99% confidence?
We need a sample of at least n.
n is found when M = 2. So
Rounding up
We need a sample size of at least 101
Parallelograms and trapezoids always do.
(Note: "Parallelograms" includes rectangles, squares, and rhombussesses.)
Any polygon with more than 4 sides <u>can</u> have at least one pair of parallel sides,
but it's not guaranteed.
Answer:
b, c, a
Step-by-step explanation:
In a triangle, the largest angle is opposite the longest side. The smallest angle is opposite the shortest side.
This triangle has 2 given angles, 50° and 60°.
We can find the measure of the third angle, x.
50 + 60 + x = 180
x + 110 = 180
x = 70
The three angles have measures 50°, 60°, and 70°.
The shortest side is opposite the smallest angle. That is side a.
The longest side is opposite the largest angle. That is side b.
The order from longest to shortest is
b, c, a
