Answer:
110
Step-by-step explanation:
Answer:
The mean is 11.5 minutes and the standard deviation is of 6.64 minutes
Step-by-step explanation:
An uniform probability is a case of probability in which each outcome is equally as likely.
For this situation, we have a lower limit of the distribution that we call a and an upper limit that we call b.
The mean is:

The standard deviation is:

Arrival time of 9:18 am and a late arrival time of 9:41 am.
9:41 is 23 minutes from 9:18. So the time is uniformily distributed between 0 and 23 minutes, so a = 0, b = 23.
Mean:

Standard deviation:

The mean is 11.5 minutes and the standard deviation is of 6.64 minutes
Answer:
2) -1
Step-by-step explanation:
it is easy
we have to first open the brackets, as it is ' - ' we have to change the sign to opposite of that of the number in the bracket and then solve it.
so the number 2 is having negative sign, we make it positive. this rule is applied only when there is a negative sign and a bracket is there.
-3-(-2)
-3+2
=-1
Answer:
We need a sample size of at least 383.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
.
The margin of error is:

85% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
How large a sample would be required in order to estimate the fraction of tenth graders reading at or below the eighth grade level at the 85% confidence level with an error of at most 0.03
We need a sample size of at least n.
n is found with 
Then






Rounding up
We need a sample size of at least 383.
Answer:
the new ones and the old ones that you didn’t delete
Step-by-step explanation: