1. No category

Statistics
2 Marks
31. You are given the following set of marks from a recent quiz:
2.5 7
13;5
/ 47
4,5''
z-7
Express the mean and median for this set of marks.
137
Mean:
Median:
4511:A.
C.-;"
• (:)" 1'C'•
r
7
./
0 11
1
1
1 11111
91,
2 Marks
32. Explain why a student might request that her course mark be calculated using a 'trimmed
mean" method.
ry e
u
Ct
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—3-1.21
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138
4 Marks
33. Jim had the following results during his recent mathematics course:
Term: 400 out of a possible 500 marks
Final Exam: 30 out of a possible 50 marks
A) Calculate Jim's final mark if the teacher weights the term and final exam marks equally.
(2 marks)
139
B) Calculate Jim's final mark if the teacher gives an 80% weight to the term and a 20%
weight to the final exam. (2 marks)
140
3 Marks
34. The following measurements represent the weights (in pounds) of players on a football
team:
Players' Weights (in pounds)
225
250
270
295
225
250
280
300
230
250
285
315
245
265
295
320
Calculate the percentile rank of a player flint weighs 250 pounds.
141
1 Mark
Lt117
13. Choose the letter that best completes the statement below.
Outliers are removed from a data set before calculating the measure of central tendency.
This measure is called the
a) mean
b) median
c) mode
trimmed mean
weighted mean
Answer:
2 Marks
14. You are given the following set of data.
10
3
10
4
5
2
9
9
2
7
7
3
8
8
3
a
33 3
A) Express the mode. (1 mark)
/0 /0
118
Answer:
B) Express-the median. (1 mark)
Answer:
7
119
5
2 Marks
120
15. A research company conducted a survey on the music preferences of Wvo groups of people.
People in Grocip A enjoyed 1A5M of the 5 songs.45epple in Group B enjoyed 3 out of
5 songs.
Explain why the\ research company ma e a weighted
enjoyinent of the mme.
2 Marks
>Az
16. A class of 20 students had a mean of 8 out of 10 on a recent quiz. The teacher added up all
of the marks and got 160 out of 200 marks for the class. The teacher decides to use a
trimmed mean, and drops two marks: a "2" and a "10". Calculate the trimmed mean for the
class.
2c
10
2
0-
2-
tr.\
121
3 Marks
17. On a recent math test, Hannah received a better mark than 16 other students in the class.
There are 25 students in the class.
122
A) Calculate Hannah's percentile rank (2 marks)
'
Le--e 6
123
B) Explain whether Hannah passed the test (1 mark)
2 Marks
33. The data below shows the amount of snow that fell during a 7-day period in Springfield,
Manitoba
:,:,'::::•Stinday);;:;r K;;ICAit4IdtSiA;;:, TFUeLsda-SC::•J Wednesday
2 cm
0 cM
1 cm
12 cm
Thursday - 'xi.FialdaY.,:,....:i1.:Satuitt'ar
4 cm
0 cM
3 cm
142
A) Starr the median daily snowfall for the period. (1 mark)
143
B) Stare the mode of daily snowfall for the period. (1 mark)
0
c
3 Marks
34. Mrs. Themark's class of 10 students had the following results (as percents) on a recent unit
test:
10
65
75
82
90
57
67
78
83
91
144
A) Mrs. Themark wants to determine the class average by calculating the trimmed mean,
by removing the highest and lowest result Calculate the trimmed mean. (2 marks)
ci I
145
B) Explain why the mark of 10% could be considered an outlier. (1 mark)
2 Marks
146
35. A student scored in the 94th percentile of her class, yet was unhappy with her test mark.
Explain how she could be unhappy with this result.
3 Marks
36. Fifty (50) members of a football team are weighed. Thomas weighs 165 pounds. Four (4)
players weigh less than Thomas.
147
A) Calculate Thomas's percentile rank. (2 marks)
ta
0
148
B) Explain how Thomas's weight compares to the weight of the other team members.
(1 mark)
/0
4 Marks
31. The scores for a unit test in mathematics are listed below.
30
45
45
55
65 i
\
70)
2
70
70
75
80
95
in 00;
A) State the median: (I mark)
I
ic C,
0
143
Median:
144
B) The teacher decides not to count the lowest mark. State whether each of the following
will increase, decrease, or have no/Chiti
' ge. (3 marks)
k-A
t
Mode:
Median:
Mean:
r i
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I
Itettx.0.../CO,
11
..
IA) 1 1 ‘
PA CA/ d Y
— ,
'7141 61,1,..AjV
a
(2
ki,.'
C- '
i — 0/.al..A A
>
CIA)
,
/1
3 Marks
145
32. On a course outline, the teacher has indicated that the course work is worth 70% of the final
mark and the exam is worth 30% of the final mark
Calculate the final mark of a student who has achieved 67% on the course work and 82% on
the final exam.
7 c
uutr (lc
0()0
3 Marks
33. In a university class of 230 students, Kegan achieved 92% on the final exam. There were
23 students who scored lower than Kegan.
146
A) Calculate Kegan's percentile rank (2 marks)
2/0
LI
147
B) The university will only give an award to the top 10% of students. Explain whether
Kegan will get an award. (1 mark)
-
//
'
'
A/
/3
2 Marks
138
31.
Given the following scores from a Grade 12 Biology class:
64
80
87
54
4{1
26
61
68
54
72
54
87
A) State the mean. (1 mark)
139
B) State the mode. (1 mark)
i
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i
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,..,/ . 1
....,_wylc
v
co-k-i, t.--, .rot,-"Xj--..\
v,
ri .z rAbikk I
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. i
,-•
Get.
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L.)
S
12
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f\I „
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7 2-
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—tic=
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onfy.
i
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1. 1,22
Vittivit'v
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A 4 LL/IA
It
2 Marks
140
32.
Three hundred (300) students wrote a math exam. Craig scored 78% on his math
exam. Calculate Craig's percentile ranking, if 204 students received a lower score
than him.
1 Mark
141
33.
Jody and Carol play on two different basketball teams. They were both ranked for
points scored on their teams.
• Jody ranks in the 90th percentile on her team.
• Carol ranks in the 75th percentile on her team.
Explain whether it can be determined which player scored more points.
2 Marks
142
34.
Tatiana is enrolled in a law class. The following table shows the average marks she
earned and the weight for each category.
Average
7f. Mark
Assignments
90
10%
Tests
65
60%
Final Exam
60
30%
Using a weighted mean, calculate Tatiana's final mark in the course.
2 Marks
143
35.
Calculate the trimmed mean by eliminating the highest and the lowest number for
the following set of data
29" )\
61
87
64
53
9
82
46
70
78
76
73