Answer:
The interval that represents the middle 68% of her commute times is between 33.5 and 42.5 minutes.
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
Approximately 68% of the measures are within 1 standard deviation of the mean.
Approximately 95% of the measures are within 2 standard deviations of the mean.
Approximately 99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean of 38 minutes, standard deviation of 4.5 minutes.
Determine the interval that represents the middle 68% of her commute times.
Within 1 standard deviation of the mean. So
38 - 4.5 = 33.5 minutes
38 + 4.5 = 42.5 minutes.
The interval that represents the middle 68% of her commute times is between 33.5 and 42.5 minutes.
A: Suppose Mr. Moore decides to use 20 seventh graders as the sample. Is this sample a random sample? Explain your reasoning.
Ans: No, because he only chose the seventh graders which is invalid since he wants to have to use the mean height which involves the 6th, 7th and 8th graders.
B: Mr. Moore decides to use a random number generator to select 20 students from the school. Suppose that when choosing 20 students using the random generator on the graphing calculator, Mr. Moore’s sample is all eighth graders. Does that mean the sample is not a random sample? Explain your reasoning.
Ans: No, it is still a random sample. Since he is using a random generator, there is a possibility that the random generator would pick all students from the 8th grade. Unlike the first one, the random generator is not biased towards any grade, it is just a coincidence.
Answer:
56
Step-by-step explanation:
102.500÷×+÷110,000
56
Answer:
Null hypothesis = 
Alternate hypothesis =
Step-by-step explanation:
Given : In a recent semester, the proportion who earned a bachelor's degree within six years was 0.395.
The president of a certain college believes that the proportion of students who enroll in her institution have a higher completion rate.
To Find : Determine the null and alternative hypotheses.
Solution:
In a recent semester, the proportion who earned a bachelor's degree within six years was<u> 0.395. </u>
Claim : the proportion of students who enroll in her institution <u>have a higher completion rate.</u>
So,null hypothesis = 
Alternate hypothesis =
Answer: ![[-3,7]](https://tex.z-dn.net/?f=%5B-3%2C7%5D)
Step-by-step explanation:
The range of a function is the set of y-values