210 because 7th graders washed 12 cars, 8th graders washed 14 cars, 6th graders washed 16 cars. Added all together and multiplied by 5, it equals 210
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:
to the fourth power, over 25 = 52 A… Get the answers you need, now! ... B. By simplifying 25 to 52 to make both powers base five and adding the exponents ... was used to simplify the expression is D. By finding the quotient of the ... rules of exponents simplify the expressions below: 2 4 3 0 4 6 4 -3 2 3 2.
Step-by-step explanation:
Answer:
B) Information about exponential notation
Step-by-step explanation:
The information on the page is about exponential notation, therefore option (B) is the most suitable.