Answer:
The 99% (two-sided) confidence interval for the true average echo duration μ is between 0 sec and 1.99 sec.
Step-by-step explanation:
We have the sample standard deviation, so we use the student t-distribution to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 101 - 1 = 100
99% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 100 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.99}{2} = 0.995. So we have T = 2.6259
The margin of error is:
M = T*s = 2.6259*0.45 = 1.18
In which s is the standard deviation of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 0.81 - 1.18. Answer in seconds cannot be negative, so we use 0 sec.
The upper end of the interval is the sample mean added to M. So it is 0.81 + 1.18 = 1.99 sec
The 99% (two-sided) confidence interval for the true average echo duration μ is between 0 sec and 1.99 sec.
Answer:
it would be 2d - 60
Step-by-step explanation:
Because if you susbtract d from 3d it would be 2d cause d is like a number in this unit
-5.2 -4.8= -10 thats your answer and it easy math.
Answer:
#9 slope is -2, y int is 3
#10 slope is 3/4, y int is 0
Avery can explain to her school principal that 85% of juniors think there is a lot of homework because several indicators have increased.
<h3>What is an indicator?</h3>
An indicator is a datum that is taken as a reference to analyze the evolution or change of a fact over time. In this case, the indicators would be:
- Weekly hours used to do homework
- Number of students with work for after school.
According to the information, it can be inferred that 85% of Junior students consider that there is an increase in homework because there were the following changes compared to last year:
- Increase in hours spent on after school homework, last year the average was 5 hours, this year it is 8 hours.
- Increase in the number of students with after school jobs, last year it was 135 students, this year it is 215 students.
From the foregoing, it can be inferred that the number of homework has increased in Junior students and that is why now 85% of them consider that homework has increased.
Learn more about indicator in: brainly.com/question/20264817
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