Name:______________________________________per.___
ROUNDING RULE:
Work Shown?:
PSU Stat – Review Worksheet: DUE Friday, 10/2
(Unit 3 Data Descriptions & Unit 4 Probability)
Round to one more decimal than occurs in the raw data
On Mean, Variance and Standard Deviation & Story Problems
Stem & Leaf PLOT:
FORMULAS:
𝑥̅ =
𝑠2 =
𝑥̅ =
𝑥1 + 𝑥2 …+ 𝑥𝑛
𝑛
= ∑
𝑋
𝜎2 =
𝑛
𝑛 ∑(𝑋 2 ) − ∑(𝑋)2
𝑠2 =
∑𝑓
𝐶𝑉𝑎𝑟 =
𝑠
𝑥̅
𝑛(𝑛−1)
𝑠 ≈
1
𝑘2
;k=
𝑛(𝑛−1)
2
𝑛 (∑ 𝑓 ∙ 𝑀𝐷 )− (∑ 𝑓 ∙ 𝑀𝐷 )2
∙ 100
Chey Chev = 1 −
𝜎 = √𝜎 2
𝑁
𝑛 ∑(𝑋 2 ) − ∑(𝑋)2
𝑠= √
𝑛(𝑛−1)
∑ 𝑓 ∙ 𝑀𝐷
∑(𝑋 − 𝜇)
Mean =
𝑟𝑎𝑛𝑔𝑒
4
𝑑𝑖𝑓𝑓𝑒𝑟𝑛𝑐𝑒
z-score =
𝑠𝑡𝑎𝑛𝑑𝑎𝑟𝑑 𝑑𝑒𝑣𝑖𝑎𝑡𝑖𝑜𝑛
𝑋− 𝑋̅
𝑆
Median =
Mode =
1.
Below are the average minutes people spend checking their
Facebook Pages at Work of FB users. Calculate the Data Values of…
Range =
12,
15,
18,
18,
15,
22,
15,
30,
12,
41,
9
Q1 =
SHOW Formulas with VALUES for CREDIT (Mean, Variance and Standard Deviation):
Q3 =
IQR =
Variance =
Standard Deviation =
Page 1
2.
Find the weighted mean for a particular student's scores on three exams if the first one was
worth 75 points and the student received a score of 70%, the second was worth 50 points and
the student received a score of 80%, and the third was worth 30 points and the student
received a score of 95%?
3. The data below shows the average commuting times of an employee at Business A.
complete the table but All pertinent steps and values need to be displayed for full credit.
Daily commuting time
Frequency = f
0 to less than 10
4
10 to less than 20
9
20 to less than 30
6
30 to less than 40
4
40 to less than 50
2
MD =
You can use the calculator to
f X MD =
f X MD2 =
Group Mean =
Modal Class =
Standard Deviation =
Page 2
FORMULAS -- 𝑃(𝐵 |𝐴) =
𝑃(𝐴 𝑎𝑛𝑑 𝐵)
𝑃(𝐴)
; P(A AND B) = P(A) x P(B);
P(A OR B) = P(A) + P(B) – P(A AND B)
1. How many possible outcomes would there be if three coins were tossed once?
2. Tree diagrams are useful for
A) illustrating the law of large numbers.
B) finding all possible outcomes in a probability experiment involving several steps.
C) showing that the outcome is the set of all possible sample spaces.
D) ordering outcomes from lowest to highest.
3. An apartment building has the following distribution of apartments:
1 bedroom
2 bedroom
3 bedroom
1st floor
3
0
1
2nd floor
1
3
2
3rd floor
1
4
1
If an apartment is selected at random, what is the probability that it is on the 2nd floor or has 2
bedrooms?
4. Given the following Venn diagram, which of the following equations could be used to calculate
the probability of either event A, event B, or event C occurring.
A)
P ( A or B or C )  P ( A)  P ( B )  P (C )
 P ( A and B )
 P ( B and C )
B)
P ( A or B or C )  P( A)  P ( B )  P (C )
 P ( A and B )
 P ( A and C )
 P ( B and C )
 P ( A and B and C )
C)
D)
P( A or B or C)  P( A)  P( B)  P(C)
 P( A and B and C)
P( A or B or C)  P( A)  P( B)  P(C)
Page 3
5. A coin is tossed 5 times.
Find the probability that all 5 tosses are tails.
6. There are 2 blue balls, 4 red balls, and 3 white balls in a bag of balls. If a person selects two of
the balls, what is the probability that the second one is blue given that the first one was white?
7. A business has seven locations to choose from and wishes to rank only the top three locations.
How many different ways can this be done?
A) 5,040
B) 210
C) 840
D) 420
8. FizzFizz soda comes in two varieties, regular and diet. If a researcher has 4 boxes of each,
how many ways can he select 2 boxes of each for a quality control test?
A) 36
B) 24
C) 15
D) 8
9. Three statistics professors and seven chemistry professors are available to be advisors to a
student organization. The student organization needs two of the professors to be advisors.
If each professor has an equal chance of being selected, what is the probability that both
professors are chemistry professors?
10. If 35 tickets are sold and 2 prizes are to be awarded, find the probability that one person will
win both prizes if that person buys exactly 2 tickets.
Page 2
Daily commuting time
0 to less than 10
4
5
20
100
10 to less than 20
9
15
135
2025
20 to less than 30
6
25
150
3750
30 to less than 40
4
35
140
4900
40 to less than 50
2
45
90
4050
N = 25
Mean
minutes
Variance
Standard deviation
minutes
Page 3