Question 664462: My final passing grade is depending on some of these problems. (I have tried working out them & I have including my work, if it is correct please let me know, if not please correct me, and if its blank, I need help!.)Please HELP!
Problem #1
(A) Classify the following as example of nominal, ordinal, interval, or ratio level of measurement, and state why it represents this level: distance between two signposts.
(B) Determine if this data is qualitative or quantitative: Brown eyes
(C) In your own line of work, give one example of a discrete and one example of a continuous random variable, and describe why each is continuous or discrete.(Points:9)
My answers: (A) Interval, measured along a scale in which each position is of equal distance from one another.
(B) qualitative-It is a variable that describes or categorizes an element of population.
(C) A discrete random variable is whether I get the flu or not, and how many days I stay home. This is a countable finite number. A continuous random variable is how many minutes after the hour it actually takes my school bus to get out of the parking lot.
Problem #2
A study is performed to discern if there is any difference in sitting heart rate between those who have two or less cups of coffee per day and those who have three or more cups per day. Subjects are chosen at random based on whether they drink two or less or three or more cups of coffee per day and their heart rates measured at the same time each day for a period of 3 months. Find the following:
I. What is the population?
II. What is the sample?
III. Is the study observational or experimental? Justify your answer.
IV. What are the variables?
V. For each of these variables, what level of measurement (nominal, ordinal, interval, or ratio) was used to obtain data from these variables?
(Points: 12)
Problem #3
Construct both an ungroup and a grouped frequency distribution for the data given below:
124 115 11 112 118 123 121 116 114 113
118 110 110 112 116 118 120 115 120 110
(Points: 10)
Problem #4
Given the following frequency distribution, find the mean, variance, and standard deviation. Please show your work.
Class …… Frequency
71-73 ….. 17
74-76 …. 8
77 –79… 12
80 – 82 .. 7
83 -85…16
(Points:10)
Problem #5
The following data lists the average monthly snowfall for January in 15 cities around the US:
42 45 8 18 45 15 31 46
3 33 2 6 32 47 36
Find the mean, variance, and standard deviation. Please show all of your work.
(Points:10)
My work: mean is a sum of sf/ sum of f
4221/63=67
SD: first calculate SSx
SSx=Sx^2f-[(Sxf)^2/n]
284103-(4221^2/63)
1296
S=sqrt(SSx/n-1)
S=sqrt(1296/(63-1)]
S=4.572
Answer by ewatrrr(24785)   (Show Source):
You can put this solution on YOUR website!
Hi,
What I redid is Problem 4, differences most likely due to my getting "60" not "63"
Did not see any work for Problem 5.
Check out 4 and 5
Class …… Frequency
71-73 ….. 17
74-76 …. 8
77 –79… 12
80 – 82 .. 7
83 -85…16
MidPT(M) f M*f M - m (M - m)^2 f(M - m)^2
72 17 1224 -5.85 34.2225 581.7825
75 8 600 -2.85 8.1225 64.98
78 12 936 0.15 0.0225 0.27
81 7 567 3.15 9.9225 69.4575
84 16 1344 6.15 37.8225 605.16
sum 60 4671 1321.65
mean 77.85 Variance 22.4
SD 4.732863826
42 45 8 18 45 15 31 46
3 33 2 6 32 47 36
42 27.26666667 14.733 217.071
45 27.26666667 17.733 314.471
8 27.26666667 -19.267 371.204
18 27.26666667 -9.267 85.871
45 27.26666667 17.733 314.471
15 27.26666667 -12.267 150.471
31 27.26666667 3.733 13.938
46 27.26666667 18.733 350.938
3 27.26666667 -24.267 588.871
33 27.26666667 5.733 32.871
2 27.26666667 -25.267 638.404
6 27.26666667 -21.267 452.271
32 27.26666667 4.733 22.404
47 27.26666667 19.733 389.404
36 27.26666667 8.733 76.271
409 4018.933
27.26666667 Variance 287.067
845.2666667 SD 16.94305167
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