MS 150 Statistics quiz 05 • Name:

1. __________ What is the probability that "our unguessable password" is p455w0rd?
2. __________ What level of measurement is the password data?
3. __________ If this was really the basis of a large scale study, what is the mode?

A convenience sample of 43 students in MS 150 Statistic fall 2007 yielded the following results:

PsychoactiveFrequencies
SubstanceNeverAbout once a monthAbout once a week A few times a weekEvery day
Betelnut without tobacco297323
Betelnut with tobacco2201317
1. __________ Consider just the first data row, the data on those who chew without tobacco. What is the probability that a student does not chew betelnut?
2. __________ Consider just the first data row, the data on those who chew without tobacco. For those who do chew, what is the mode?
3. __________ Consider just the second data row, the data on those who chew with tobacco. For those who do chew, what is the mode?
4. Considering the above two mode results, what impact does tobacco appear to have on betelnut chewing habits?
Bin upper
limit for
number of
elements (x)
Frequency f Rel freq, p(x)x*p(x)
5 5 0.04 0.18
10 12 0.09 0.88
15 30 0.22 3.31
20 50 0.37 7.35
25 25 0.18 4.60
30 9 0.07 1.99
35 5 0.04 1.29
Sums: 136 1.00 19.60

The data in the table is adapted from a study done by Eelmine Järgmine on the number of elements found in a web page. A larger study by Google confirms this data. Although the data is technically not continuous data, use the table to report the mean number of different html elements found on a typical Internet web page.

1. __________ What is the mean number of elements found on a typical web page?