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FOM11
Chapter 5 Review A
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____
1. Environment Canada compiled data on the number of lightning strikes per square kilometre in Alberta and
British Columbia towns from 1999 to 2008.
0.42
0.04
0.81
0.40
0.03
0.74
0.28
0.03
0.70
0.23
0.03
0.66
0.13
0.02
0.61
0.12
0.01
0.58
0.10
0.00
0.49
0.07
1.08
0.43
0.05
0.91
0.42
0.04
0.88
Determine the mean, to two decimal places.
____
____
____
____
a.
b.
c.
d.
0.12
0.00
0.36
0.60
a.
b.
c.
d.
about 95%
100%
about 68%
about 50%
a.
b.
c.
d.
17.5%
13.5%
27%
32%
a.
b.
c.
d.
±3%
±6%
±5%
±4%
a.
b.
c.
d.
3000
1000
2000
It is impossible to tell.
2. A set of data is normally distributed. What percent of the data is greater than the mean?
3. The ages of participants in a bonspiel are normally distributed, with a mean of 40 and a standard deviation of 10
years. What percent of the curlers are between 20 and 30?
4. The results of a survey have a confidence interval of 28% to 34%, 19 times out of 20.
Determine the margin of error.
5. Which sample size will have the least margin of error?
____
6. A pear orchard has 40 trees with these heights, given in inches.
110
105
83
84
104
92
95
98
88
92
80
81
115
88
106
92
97
103
100
93
98
93
93
102
92
87
117
92
75
102
83
107
122
92
115
86
89
98
105
125
What value goes in the second row of this frequency table?
Height (in.)
70–80
80–90
90–100
100–110
110–120
120–130
____
a.
b.
c.
d.
Frequency
2
15
9
3
2
10
12
9
11
7. Which histogram represents the following test scores?
Geography Test 4 Scores (our of 100)
98
82
75
66
62
95
81
72
64
58
92
80
72
62
55
85
76
72
62
55
85
75
67
62
41
a.
c.
b.
d.
____
8. At the end of a bowling tournament, three friends analyzed their scores.
Erinn’s mean bowling score is 92 with a standard deviation of 14.
Declan’s mean bowling score is 130 with a standard deviation of 18.
Matt’s mean bowling score is 116 with a standard deviation of 22.
Who had the highest scoring game during the tournament?
____
a.
b.
c.
d.
Impossible to tell.
Erinn
Matt
Declan
a.
b.
c.
d.
73.5
66
70
79.5
9. A teacher is analyzing the class results for a physics test. The marks are normally distributed with a mean (µ) of
76 and a standard deviation () of 4.
Determine Ram’s mark if he scored µ – 2.5.
____ 10. Which set is normally distributed?
0–10
10–20
Interval
84
72
Set A.
13
57
Set B.
35
35
Set C.
64
48
Set D.
a.
b.
c.
d.
20–30
75
91
35
38
30–40
75
96
45
72
40–50
72
43
55
55
50–60
64
20
55
87
Set D.
Set B.
Set C.
Set A.
Short Answer
11. Aisha researched the average daily temperature in her city.
Average Daily Temperature in Victoria, BC
Month
Jan. Feb. Mar. Apr. May Jun.
average daily 3.4
5.8
7.3
8.7
12.0 14.4
temperature
(°C)
Determine the range of the data.
Jul.
18.1
Aug.
16.9
Sep.
13.4
Oct.
9.4
Nov.
5.8
Dec.
3.7
12. A teacher is analyzing the class results for a physics test. The marks are normally distributed with a mean (µ) of
76 and a standard deviation () of 4. Sketch the normal curve for the test.
13. Determine the z-score for the given value.
µ = 9.3,  = 0.4, x = 8.8
14. Determine the percent of data between the following z-scores:
z = 0.34 and z = 1.70.
15. Determine the approximate mean for this data:
82–86
86–90
90–94
Interval
5
3
8
Frequency
94–98
20
98–102
11
102–106
1
Problem
16. An apple orchard has 32 trees with these heights, given in inches.
116
90
91
99
114
110
124
102
82
89
104
102
95
105
118
118
110
97
92
93
91
116
101
101
116
86
101
83
117
93
132
104
a) Construct two different histograms of this data: one with intervals of five and one with intervals of 10.
b) Compare your histograms.
17. A tile company produces floor tiles that has an average thickness of 55 mm, with a standard deviation of
0.6 mm. For premium-quality floors, the tiles must have a thickness between 54 mm and 55 mm. What
percent, to the nearest whole number, of the total production can be sold for premium-quality floors?
18. In a population, 50% of the adults are taller than 172 cm and 10% are taller than 190 cm. Determine the mean
height and standard deviation for this population.
FOM11 Chapter 5 Review A
Answer Section
MULTIPLE CHOICE
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
C
D
B
A
A
C
B
A
B
B
SHORT ANSWER
11.
12.
13.
14.
15.
14.7°C

–1.25
32.23%
Midpoint
Frequency
83.5
5
87.5
3
91.5
8
95.5
20
99.5
11
103.5
1
mean = 94.17, standard dev = 4.99
PROBLEM
16.
a) I can use this frequency table for both histograms:
Height (in.)
Frequency
80–84
2
85–89
90–94
95–99
100–104
105–109
110–114
115–119
120–124
125–129
130–134
2
6
3
7
1
3
6
1
0
1
b) e.g., The histogram with intervals of five gives more detailed information, but it takes longer to organize and draw. The histogram with intervals of
10 does not contain as much information (the one tree in 130–139 could be 130 in. tall or 139 in. tall), but it still gives you a fair idea of the distribution
and was faster to construct.
17.
Determine the two z-scores:
The z-scores are –1.67 and 0.
Using the z-score table, 50.00% – 4.75% = 45.25% of the data is between these two z-scores.
About 45% of the total production can be sold for premium-quality floors.
18.
Using the z-score table, 50% or 0.50 corresponds to a z-score of 0.0. This is the mean height of the population. So the mean height is 172 cm.
Then 10% of the population to the right of 190 cm is 90% or 0.90 of the population to the left of 190 cm. Using the z-score table, 0.90 corresponds to a
z-score of 1.28.
The standard deviation is 14.0 cm.