Question

0
0
2
0
5
3
1
12
0
0
0
1
6
0
1
1
2
8
1
3
1
6
2
4
0
16
17
0
8
0
3
0
0
1
2
5
2
0
2
1
5
0
7
0
1
0
0
1
0
0
3
1
9
4
1
3
0
1
1
1
0
7
1
9
2
0
1
1
1
1
7
2
7
1
2

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1. (a) What type of data is this? That is, is it: Qualitative Nominal, Qualitative Ordinal, Quantitative Discrete, or Quantitative Continuous data?
   (b) Explain WHY you say it is that type.
2. What is the probability P(x > 2)? Express the probability as a decimal, rounded to three places.
3. Find P(x is no more than 12). Express the probability as a decimal, rounded to three places.
4. Does the probability in Question 3 indicate that it was an unusual event? Look up the concept of an unusual event in the textbook, if necessary, before answering! Explain your answer in a full sentence. Be sure you are specific about the value of the probability in Question 3 in comparison to the criterion for an unusual event.
5. In your opinion, does the store need more checkout lanes? Cite specific probabilities from your distribution to justify your written answer; do not just answer yes/no.

Answer 1

For the given data
0
0
2
0
5
3
1
12
0
0
0
1
6
0
1
1
2
8
1
3
1
6
2
4
0
16
17
0
8
0
3
0
0
1
2
5
2
0
2
1
5
0
7
0
1
0
0
1
0
0
3
1
9
4
1
3
0
1
1
1
0
7
1
9
2
0
1
1
1
1
7
2
7
1
2

a. The data is obviously discrete, and hence not continuous
also, the data is numeric so it is not qualitative but Quantitative
hencethe data us Quantitative Discrete

b. Is is this type as it is numeric (hence not qualitative but quantitative) and discrete ( as it is not continuous)
c. P(x > 2) = n(x > 2)/n
n = 75
counting the numbers we get
0's = 22
1's = 21
2's = 9
3's = 5
4's = 2
5's = 3
6's = 2
7's = 4
8's = 2
9's = 2
12's = 1
16's = 1
17's = 1
total, n = 75
hence
P(x > 2) = (75 - 22 - 21 - 9)/75 = 0.3066666667

d. P(x <= 12) = (75 - 1 - 1)/75 = 0.973
e. since the probability of P(x <=12) is close to 1, it is not an unusual event
f. Now, since we can see that there are more numbers at 0's and 1's while others have fewer numbers
hence since the variation of data is high, we can say that the store does not need more checkout lanes but careful management of the available lanes