MAST30015 Statistics for Mechanical Engineers | Semester 2, 2010
Answers
Quiz 6
(Q6.1)
(Q6.2)
(Q6.3)
C
E
C
(Q6.4)
(Q6.5)
[ = y -intercept = 30; so estimate of mean is 30. ];
[ = slope = 10; so estimate of variance is 102 = 100];
ln
[ ln L = 5 + 10 ln , L

MAST30015 Statistics for Mechanical Engineers | Semester 2, 2010
Answers
Quiz 5
(Q5.1)
(Q5.2)
(Q5.3)
(Q5.4)
D
[ ordered sample: 0,0,1,1,1,1,2,2,. . . ];
[ freq(X 2) = 12, so F (2) = 12 ];
20
[ since X is continuous, the cells are (0.95 < x < 1.45), (1.45

620.370 Statistics for Mechanical Engineers | Semester 2, 2010
Homework set 4
Problems to be discussed at next week's tutorial: Quiz 4; 61, 67, 77, 85.
Homework questions
Questions 4.1 & 4.2 refer to the following information:
Y
4.1
is a continuous random

620.370 Statistics for Mechanical Engineers | Semester 2, 2010
Answers 2
21.(b') E(X ) = 12.5, sd(X ) = 10.94 = 3.31.
approximate 95% probability interval = (7.5 6.62) = (5.9, 19.1) = (6 X 19).
var(X ) > var(X), and so its probability interval is a bit wi

620.370 Statistics for Mechanical Engineers | Semester 2, 2010
Homework set 2
Problems to be discussed at next week's tutorial: Quiz 2; 21*, 28, 31, 34.
d
*21.(b') Let X = Bi(100, 0.125). Find the mean and variance of X and a 95% probability
interval for

MAST 30015: Statistics for Mechanical Engineers | Semester 2, 2010
Homework set 1
Problems to be discussed at next week's tutorial: Quiz 1; 6, 7, 8, 11.
Homework questions
The rst ve questions are multiple-choice questions, for each of which exactly one o

620.370 Statistics for Mechanical Engineers | Semester 2, 2010
Homework set 3
Problems to be discussed at next week's tutorial: Quiz 3; 37, 42, 50, 57.
Homework questions
3.1 The random variable X has probability density function f (x) = x/50, (0 < x < 10

620.370 Statistics for Mechanical Engineers Semester 2, 2010
Answers to Homework 10
Quiz 10 answers:
1. D.
[ There are four treatments each applied once in six blocks;
so se(i j ) =
y y
0.87( 1 + 1 ) = 0.5385 CI.width = 22.1310.5385 = 2.30 ]
6
6
error.MS

MAST30015 Statistics for Mechanical Engineers | Semester 2, 2010
Homework set 5
Problems to be discussed at next week's tutorial: Quiz 5; 88, 89, 92 (91).
Homework questions
Questions 5.1cfw_5.2 refer to the following information:
A random sample of twent

MAST 30015 Statistics for Mechanical Engineers | Semester 2, 2010
Answers
Quiz 8
(Q8.1)
(Q8.2)
(Q8.3)
(Q8.4)
B
(Q8.5)
C
B
E
D
[ denitions: normality of the population is required ];
d
[ power = Pr(X 14), where X = Bi(200.75); power = 1 0.214 = 0.786. ];
[

MAST30015 Statistics for Mechanical Engineers | Semester 2, 2010
Homework set 6
Problems to be discussed at next week's tutorial: Quiz 6; 107, 102, 122, 116.
Homework questions
Questions 6.1cfw_6.3 refer to the following information:
A random sample of 10

MAST 30015 Statistics for Mechanical Engineers Semester 2, 2010
Answers
Quiz 7
(Q7.1) B
[ using the diagram in the tables, or MATLAB. ];
(Q7.2) A
[ p = 0.1; 95% CI: 0.1 1.96
1.96
10
1.96
n
0.10.9
100
= (0.0412, 0.1588). ];
n = 1.96 = 2.48 10 = 2 10. ];
1.