9 more than the product of 51 And a number t
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Answer:
We conclude that the mean waiting time is less than 10 minutes.
Step-by-step explanation:
We are given that a public bus company official claims that the mean waiting time for bus number 14 during peak hours is less than 10 minutes.
Karen took bus number 14 during peak hours on 18 different occasions. Her mean waiting time was 7.8 minutes with a standard deviation of 2.5 minutes.
Let = <u><em>mean waiting time for bus number 14.</em></u>
So, Null Hypothesis, :
10 minutes {means that the mean waiting time is more than or equal to 10 minutes}
Alternate Hypothesis, :
< 10 minutes {means that the mean waiting time is less than 10 minutes}
The test statistics that would be used here <u>One-sample t test statistics</u> as we don't know about the population standard deviation;
T.S. = ~
where, = sample mean waiting time = 7.8 minutes
s = sample standard deviation = 2.5 minutes
n = sample of different occasions = 18
So, <u><em>test statistics</em></u> = ~
= -3.734
The value of t test statistics is -3.734.
Now, at 0.01 significance level the t table gives critical value of -2.567 for left-tailed test.
Since our test statistic is less than the critical value of t as -3.734 < -2.567, so we have sufficient evidence to reject our null hypothesis as it will fall in the rejection region due to which <u>we reject our null hypothesis</u>.
Therefore, we conclude that the mean waiting time is less than 10 minutes.
Note: You missed to add the dot plots chart. As I found the chart after a little research. Thus, I am attaching it and based on that dot plot chart I am solving the question which anyways would clear you concept.
Answer:
'There are about 2 more students in each class at Oak Middle School than at Poplar Middle School' is the correct statement.
Step-by-step explanation:
From the diagram, it is clear that
The data set containing Poplar Middle School:
20 20 20 21 21 21 21 21 22 22 22 22 22 22 22 23 23 23 23 24
The mean of a data set is the sum of the terms divided by the total number of terms. Using math notation we have:
The data set containing Oak Middle School:
20 21 21 22 22 23 23 23 23 24 24 24 25 25 26 26 27 27 28 29
The mean of a data set is the sum of the terms divided by the total number of terms. Using math notation we have:
So, the difference in mean will be:
Therefore, 'there are about 2 more students in each class at Oak Middle School than at Poplar Middle School' is the correct statement.