MA 102 Computer Statics and Research
Activity 2.
1. A survey was given to Information Technology students to find out how many hours per week they
would need to create and debug the program. The sample responses were separated by gender.
Determine the mean, range, variance, and standard deviation of each group (15pts)
Group A (Female)
15
25
12
7
3
32
17
16
9
24
Group B (Male)
30
15
21
12
26
20
5
24
18
10
Answers:
Group A (Female)
Group B (Male)
Mean
Solution:
Mean= (A1 + A2….+ An)/n
= (15+25+12+7+3+32+17+16+9+24)/10
Mean = 16
Solution:
Mean= (A1 + A2….+ An)/n
= (30+15+21+12+26+20+24+18+10)/10
Mean = 18.1
Range
Range = Highest Value – Lowest Value
= 32-3
Range = 29
Range = Highest Value – Lowest Value
= 30-5
Range = 25
Variance
Standard
Deviation
2. The spread, or the distance, between a variable's lowest and highest values. To get the range for a
variable, you subtract its lowest value from its highest value(10pts).
Class A--IQs of 13 Students
102
115
128
109
131
89
98
106
140
119
93
97
110
Class B--IQs of 13 Students
127
162
131
103
96
111
80
109
93
87
120
105
109
Answer:
RANGE
Class A--IQs of 13 Students
Class B--IQs of 13 Students
89, 93, 97, 98, 102, 106, 109, 110, 115, 119,
128, 131, 140
80, 87, 93, 96, 103, 105, 109, 109, 111, 120,
127, 131, 162
Range = Highest Level Value- Lowest Level
Value
= 140 – 89
Range = Highest Level Value- Lowest Level
Value
= 162 – 80
Range = 51
Range = 82
5. How can assessment score data be summarised? ( 20pts)
Exam points for 60 students (marked out of 65)
Summary statistics
a.
b.
c.
d.
Mean=
Large SD =
Small SD =
For assessment scores, mean =?
6. Mr. Riven Timbal wants to study the general performance developments among his grade-nine
mathematics students, to evaluate student learning and his instruction. He gives a mid-term language arts
exam and obtains the following scores for his students:
95
91
100
96
92
91
87
84
70
65
96
65
56
86
43
65
22
40
93
Mr. Timbal creates a frequency distribution table to evaluate those scores to organize the test data. The
obtained scores are listed in order from highest to lowest. (50pts)
-
Calculate the Mean, Median, and Mode
Solution:
Mean
Mean= (A1 + A2….+ An)/n
= (22 + 40 + 43 + 56 + 65 + 65 + 65 + 70 + 84 + 86 + 87 + 91 + 91 +
92 + 93 + 95 + 96 + 96 + 100)/19
Mean = 75.63
Median
22, 40, 43, 56, 65, 65, 65, 70, 84, 86, 87, 91, 91, 92, 93, 95, 96, 96, 100
Median= 86
Mode
22, 40, 43, 56, 65, 65, 65, 70, 84, 86, 87, 91, 91, 92, 93, 95, 96, 96, 100
Mode = 65
-
Representation of the Mean, Median, and Mode on a Curve
-
Calculate the Standard Deviation, Range of this distribution score.
Standard Deviation
Range
22, 40, 43, 56, 65, 65, 65, 70, 84, 86, 87, 91, 91, 92,
93, 95, 96, 96, 100
Range = Highest Level Value- Lowest Level Value
= 100 – 22
Range = 78
-
Graphic Displays of Distributions
Please email your answers at jackielou.madlos@sjit.edu.ph