Section 3.1 Measures of Central Tendency
Practice this one I got wrong on the homework the better describes the weight because the distribution is
mean symmetric.
see last part in Homework 11 and lecture time 8:00 all you do is take the tap water mean and substract away the bottle water mean on statcrunch so
7.522-5.219=2.303
Homework 12 The following data represent the pulse rates (beats per minute) of nine students enrolled in a statistics course. Treat the nine students as a population. Complete parts (a) to (c) (a) Determine the population mean pulse. The population mean pulse is approximately enter your response here beats per minute. (Type an integer or decimal rounded to the nearest tenth as needed.)
a.) 72.8
Question 13 Homework question see homework question
The best measure of the central tendency is the Median. Explanation: Step 1: Given that, Histogram is provided with some shape of the given frequency curve. Step 2: Here frequency curve is negatively skewed, because frequencies are lacking in the left side of the middle value. Step 3: Usually, If the frequency curve is bell shaped and symmetrical, then mean is the best measure of central tendency. In this case mean, median and mode are considered. If the frequency curve is not symmetrical (left or right skewed), then median is the best measure of central tendency. Since At the left skewed, mean < median < mode. At the right skewed, mean > median> mode. If we observe the above relation in case of skewed data, median would be middle and central representative value. Here mean and mean and mode are not suitable for skewed data series. Step 4: Therefore, Median is the best measure for this left skewed data. Explanation: Please refer the solution above if you have any doubt then please leave a comment. I have given the detailed explanation in the above image
Homework number 6 3.1 For a large sporting event the broadcasters sold 68 ad slots for a total revenue of $131 million. What was the mean price per ad slot? Part 1 The mean price per ad slot was $ fill in the blank million. (Round to one decimal place as needed.)
The mean is one of the measures of central tendency and it gives an idea about the center of the data. To find the mean price per ad slot, we have to divide the total revenue of sporting event by the number of ad slots sold. Now the mean price per ad slot is: Mean price per ad slot = Total Revenue Number of ad slots/Number of ad slots being sold = 131/68 =1.9 Explanation: The mean of the random variable is found by dividing the sum of all values by the number of values.
(c) Determine if the means of samples 1 and 2 overestimate, underestimate, or are equal to the population mean. The mean pulse rate of sample 1 ▼ over estimates is equal to underestimates the population mean. so now they want you to compare those numbers above to the population mean they see the 74 is bigger so the overestimate and the 73 to the 72.8 and both was an overestimate
((c) Determine if the means of samples 1 and 2 overestimate, underestimate, or are equal to the population mean. The mean pulse rate of sample 1 overestimates the population mean. Part 5 The mean pulse rate of sample 2 overestimates the population mean
Question 9 on the Homework Lecture time 6:36 A concrete mix is designed to withstand 3000 pounds per square inch (psi) of pressure. The following data represent the strength of nine randomly selected casts (in psi). 3970, 4090, 3200, 3000, 2930, 3840, 4090, 4030, 3610 Compute the mean, median and mode strength of the concrete (in psi). Question content area bottom Part 1 Compute the mean strength of the concrete. Select the correct choice below and, if necessary, fill in the answer box to complete your choice. A. The mean strength of the concrete is enter your response here psi of pressure. (Round to the nearest tenth as needed.) B. The mean does not exist.
3640 according to statcrunch A 3840 according to statcrunch A
Compute the median strength of the concrete. Select the correct choice below and, if necessary, fill in the answer box to complete your choice. A. The median strength of the concrete is 38403840 psi of pressure. (Round to the nearest tenth as needed.) Your answer is correct. B. The median does not exist Compute the mode strength of the concrete. Select the correct choice below and, if necessary, fill in the answer box to complete your choice. A. The mode of the strengths of the concrete is enter your response here psi of pressure. (Round to the nearest tenth as needed.) B. The mode does not exist.
4090 A
(b) Suppose the pH of 7.10 in tap water was incorrectly recorded as 1.70 How does this affect the mean? the median? What property of the median does this illustrate? If the pH of 7.10 in tap water was incorrectly recorded as 1.70, the mean pH would be (Round to three decimal places as needed.) Part 10 If the pH of 7.10 in tap water was incorrectly recorded as 1.70, the median pH would be (Round to three decimal places as needed.) Part 11 What property of the median does this illustrate? A. It illustrates the resistance of the median. B. It illustrates that the median divides the bottom 50% of the data from the top 50%. C. It illustrates the non-resistance of the median. D. It does not illustrate any property of the median.
7.071 7.495 A.) meaning that error didn't change the place of our median you see it's still 7.495 there but dramatically changed the value of the mean 7.522
(b) Determine the sample mean pulse of the following two simple random samples of size 3. Sample 1: Kevin, Crystal, Clarice Sample 2: Janette, Tammy, Jeff The mean pulse of sample 1 is approximately enter your response here beats per minute. (Round to the nearest tenth as needed.) The mean pulse of sample 2, is approximately enter your response here beats per minute. now we go to the 4th column in statcrunch lecture time 10:14 I need Kevin, Clarice, Crystal so Kevin is a 65, and Clarice is a 85,Crystal is 72 so next we go to column 5 and do Jenette, Tammy, Jeff Jenette 73, Tammy, 62, Jeff 84 now .1) stat 2) summary stats 3)columns 4) In select column tell it 4 and 5 5) tell it the mean and hit compute and there is your answer
74 73
Is the trimmed mean resistant? A. No, because extreme values affect it substantially. B. No, because extreme values do not affect it. C. Yes, because extreme values do not affect it. D. Yes, because extreme values affect it substantially.
C
Homework question 10 in lecture homework help also time 6:47 For the histogram on the right determine whether the mean is greater than, less than, or approximately equal to the median. Justify your answer.
Look at slide 19 and Homework question
Comment on the role that the number of observations plays in resistance. A. As the sample size increases, the impact of the misrecorded data on the mean increases. B. As the sample size increases, the impact of the misrecorded data on the mean decreases. C. As the sample size increases, the impact of the misrecorded data on the mean remains the same.
The impact of mis recorded data (or outliers) on the mean of a dataset is related to the sample size in an inversely proportional manner. A. As the sample size increases, the impact of the mis recorded data on the mean remains the same. Explanation: This statement is incorrect. The mean is sensitive to every value in the dataset, including outliers or mis recorded data. However, as the sample size increases, the overall impact of any single is mis recorded data point on the mean is diluted because the sum of all data points in the numerator of the mean formula is divided by a larger number (the increased sample size). Step 2 B. As the sample size increases, the impact of the mis recorded data on the mean increases. Explanation: This statement is incorrect. Intuitively, you might think that adding more data could amplify discrepancies, but in the case of the mean, the opposite is true when it comes to outliers or mis recorded data. As the sample size grows, the relative contribution of any single data point (including outliers) to the total sum decreases, thus diminishing its impact on the mean. C. As the sample size increases, the impact of the mis recorded data on the mean decreases. Explanation: This statement is correct. When the sample size increases, the denominator in the mean calculation increases. If the mis recorded data is not changing (i.e., the amount of mis recorded data does not increase with the sample size), its absolute impact on the sum (numerator) remains constant while the denominator (sample size) increases. This leads to a decrease in the relative impact of the mis recorded data on the calculated mean.
Homework question 16 lecture time 14:43 this one is about mode categorical data qualitative categorical data it's no longer quantitative because it's no longer working on numbers but we can still do this in statcrunch open statcrunch go to stat tables and frequency tell it where the numbers are in select column choose frequency in the statistics box hit compute and there it is A sample of 20 registered voters was surveyed in which the respondents were asked, "Do you think Chang, Johnson, Ohm, or Smith is most qualified to be a senator?" The results of the survey are shown in the table. (a) Determine the mode candidate (b) Do you think it would be a good idea to rotate the candidate choices in the question? Why? A. Yes, to avoid response bias B. Yes, to confuse the respondents C. Yes, to make the resulting counts all closer to each other D. There is no need to rotate the choices
To determine the mode candidate: Explanation: The mode in a set of data is the value that appears most frequently in the data set. For example: Let's consider a data: 2,3,2,5,6,8,10,2,5,6,3 In this example the mode is 2. Because it appears frequently which is 3 times. Compared to others numbers which appeared only for 1 and some 2 times. Step 2 Now let's find the mode in our case: Explanation: To determine the mode candidate first, count the number of votes for each candidate got. Then the candidate who got highest number of votes is the mode candidate. From the result let's count the number of voters for each candidate: Change: 3 votes Johnson: 4 votes Ohm: 8 vote Smith 5 votes. From the above results Smith got maximum number of votes which is 8 votes. Therefore, the mode candidate is Ohm. b.) A is correct
Question 7 on Homework lecture time 3:52 in homework help The median for the given set of six ordered data values is 29.5. 5 12 27_41 49 What is the missing value? Part 1 The missing value is enter your response here.
To find the missing value in the ordered set of data, you need to understand the concept of the median. The median is the middle value in a data set when the data is arranged in ascending or descending order. In the given dataset: 5, 12, 27, _, 41, 49 Explanation: The median is 29.5, which means it is the value that separates the lower half from the upper half of the data. Since there are six data values, the median is the average of the third and fourth values when the data is arranged in ascending order. = A +c = b Step 2 Let's assume the missing value is x. The ordered set becomes: 5, 12 ,x ,27 ,47 ,49 Now, arrange the data in ascending order: 5 ,12 ,27 ,x ,47 ,49 The median is the average of the third and fourth values, which are 27 and x explanation Median = 27+x/2 Given that the median is 29.5 27+ x /2= 29.59(2) Solving for x x+27= 59 -27=59-27 x = 32 So, the missing value is 32.
lets look at the question we ask high school student How many days in the past week have you consumed an alcoholic beverage?" it's illegal for them to consume alcohol beverages so Yes it is c
Yes, the survey suffers from response bias because it would be difficult to achieve truthful responses to this type of question unless the identity of the respondents is anonymous.
Select the correct choice below and fill in any answer boxes in your choice. A. For tap water, the mode pH is enter your response here. (Round to three decimal places as needed. Use a comma to separate answers as needed.) B. There is no mode. Select the correct choice below and fill in any answer boxes in your choice. A. For bottled water, the mean pH is enter your response here. (Round to three decimal places as needed.) B. The mean does not exist Select the correct choice below and fill in any answer boxes in your choice. A. For bottled water, the median pH is (Round to three decimal places as needed.) B. The median does not exist Select the correct choice below and fill in any answer boxes in your choice. A. For bottled water, the mode pH is enter your response here. (Round to three decimal places as needed. Use a comma to separate answers as needed.) B. There is no
a. 7.470 a. 5.219 a. 5.220 a. 5.360
The acidity or alkalinity of a solution is measured using pH. A pH less than 7 is acidic; a pH greater than 7 is alkaline. The accompanying data represent the pH in samples of bottled water and tap water. Complete parts (a) and (b). Click the icon to view the data table. Part 1 (a) Determine the mean, median, and mode pH for each type of water. Comment on the differences between the two water types. Select the correct choice below and fill in any answer boxes in your choice. A. For tap water, the mean pH is (Round to three decimal places as needed.) B. The mean does not exist. Select the correct choice below and fill in any answer boxes in your choice. A. For tap water, the median pH is enter your response here. (Round to three decimal places as needed.) B. The median does not exist.
a. 7.522 a. 7.495
What can be said about the differences between the two types of water? A. There are no differences between the two types of water. B. Bottled water is more acidic than tap water. Your answer is correct. C. Tap water is more acidic than bottled water. D. There is not enough information to determine a conclusion
b
Slide 5 Lecture time 4:19 Examples of Mean, Median, and Mode Slide 5 Lecture time 4:25 Technical term is the Mean Is also known as the word average see slide5 slide 5 Lecture time 4:43 Median is a little bit different it is the Middle in order to compute the median you have to arrange the numbers in descending order and the Median is just the middle of the data set. slide 5 Lecture time 4:57 Mode is the number that occurs the most Slide 5 Lecture time 5:02 range we will talk about that in section 3.2 is just the difference the subtraction between the highest number and the smallest number right now just focus on the mean, median, and the mode
fyi
Compute the mode cost of repair. Select the correct choice below and, if necessary, fill in the answer box to complete your choice. A. The mode cost of repair is $enter your response here. (Round to the nearest cent as needed.) B. The mode does not exist
using statcrunch B
Homework 8 in homework help lecture time 4:59 what they want out of this problem is they want the mean, the median, and the mode An insurance company crashed four cars of the same model at 5 miles per hour. The costs of repair for each of the four crashes were $438, $403, $478, and $242 . Compute the mean, median, and mode cost of repair. Question content area bottom Part 1 Compute the mean cost of repair. Select the correct choice below and, if necessary, fill in the answer box to complete your choice. A. The mean cost of repair is $enter your response here. (Round to the nearest cent as needed.) B. The mean does not exist. Compute the median cost of repair. Select the correct choice below and, if necessary, fill in the answer box to complete your choice. A. The median cost of repair is $? your response here. (Round to the nearest cent as needed.) B. The median
using statcrunch A answer is 390.25 next question using statcrunch the answer is A 420.5
Question 14 Homework question see lecture 11:22 this section is about making histograms open stat crunch before we start look at any of these pictures and magnify it you see how it starts at 0.78 and you see that this is 0.84 and thats one, two, three steps so that distance between 0.78 and 0.84 is 0.06 divided by 3 is 0.02 so it's starting at 0.78 and the widths are 0.02 your numbers may be randomize different but try to think about the logic of what he is doing starts at 0.78 each bar has a width of 0.02 Now export it statcrunch Open statcrunch go to graph not stat Histogram tell it where the numbers are example in select columns var1 now you see where it says bins start it at whatever your number starts at 0.78 width 0.02 then hit compute so you are trying to find the histogram that looks like this
which is A
