Answer:
The sample mean is
b.3.55
The margin of error is
0.32
Step-by-step explanation:
Deep explanation about a confidence interval
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 M as such
In which 
is the standard deviation of the population and n is the size of the sample.
The lower end of the interval is the mean subtracted by M. So it is 6.4 - 0.3944 = 6.01 hours.
The upper end of the interval is the mean added to M. So it is 6.4 + 0.3944 = 6.74 hours.
In this problem:
The deep explanation is not that important.
We just have to recognize that the interval has a lower end and an upper end. The distance from both the upper and the lower end to the mean is M. This means that the sample mean is the halfway point between the lower end and the upper end.
The margin of error is the distance of these two points(lower and upper end) to the mean.
In our interval
Lower end: 3.23
Upper end: 3.87
Sample mean
So the correct answer is:
b.3.55
The margin of error is
3.87 - 3.55 = 3.55 - 3.23 = 0.32
Answer:
4. 27
Step-by-step explanation:
11-10=1 which is <=16
15-10=5 which is <=16
26-10=16 which is <=16
27-10=17 which isn't <=16
Therefore 27 doesn't satisfy the inequality
Define unit vectors along the x-axis and the y-axis as
respectively.
Then the vector from P to Q is
In component form, the vector PQ is (-8,5).
The magnitude of vector PQ is
√[(-8)² + 5²] = √(89) = 9.434
Answer:
The vector PQ is (-8, 5) and its magnitude is √89 (or 9.434).
The minute hand has swept through 46 minutes on the clock. You have to set up a ratio to solve this:
You can compare the 60 minutes on a clock to 360 degrees because 60 minutes on a clock is one whole rotation. So then, you cross multiply and simplify:
Therefore, the minute hand has swept through an angle with a measure of 276 degrees.
Answer:
D. The pH indicates how acidic or basic a solution is.
Step-by-step explanation:
The range goes from 0 to 14, with 7 being neutral.
