THE UNIVERSITY OF DODOMA
COLLEGE OF NATURAL AND MATHEMATICAL SCIENCES
DEPARTMENT OF BIOLOGY
COURSE: Biostatistics I COURSE CODE: BI 215 GROUP ASSIGNMENT
Hypothesis testing
1. Body temperatures ( measured in C) twenty five intertidal crabs placed in air at 24.3 c: 25.8,
24.6, 26.1, 22.9, 25.1, 27.3, 24.0, 24.5, 24.5, 23.9, 26.2, 24.3, 24.6, 23.3, 25.5, 28.1, 24.8, 23.5,
26.3, 25.4, 25.5, 23.9, 27.0, 24.8, 22.9, 25.4. Test if the twenty five body temperatures came
from a population whose mean is 24.3 C ( = 0.05)
2. Weight change of twelve rats after being subjected to a regime of forced exercise. Each weight
change ( in g ) is the weight after exercise minus the weight before.
1.7, 0.7, -0.4, -1.8, 0.2, 0.9, -1.2, -0.9, -1.8, -1.4, -1.8, -2.0
Test whether the exercise has significant weight loss ( = 0.05)
3. A consumer group is concerned with fat content of a certain grade of steakburger submit to an
independent laboratory a random samples of 12 steakburger for analysis. The percent of fat in
each steakburgers is as follows
21, 18, 19, 16, 18, 24, 22, 19, 24, 14, 18, 15
4. The manufacturer claims that the mean fat content of this grade is less than 20%. Assuming
that percentage fat content to be normally distributed with standard deviation of 3, carryout the
statistical hypothesis test in order to advise the consumer group as the validity of the
manufacturers claim
5. The data are weight changes of humans, tabulated after administration of a drug proposed to
result in weight loss. Each weight change (in kg) is the weight after minus weight before drug
administration ( = 0.05)
0.2, -0.5, -1.3, -1.6, -0.7, 0.4, -0.1, 0.0, -0.6, -0.6, -1.1, -1.2, -0.8
6. In processing grain in brewering industry, the percentage extract recovered is measured. A
particular brewing introduces a new source of grain, and percentage extract on 11 eleven
separate days as follows
95.2, 93.1, 93.5, 95.9, 94.0, 92.0, 94.4, 93.2, 95.5, 92.3, 95.4
Test the hypothesis that the true mean percentage extract recovered is 95.0 %. What assumption
you have made in carrying out your test?
COLLEGE OF NATURAL AND MATHEMATICAL SCIENCES
DEPARTMENT OF BIOLOGY
COURSE: Biostatistics I COURSE CODE: BI 215 GROUP ASSIGNMENT
Hypothesis testing
1. Body temperatures ( measured in C) twenty five intertidal crabs placed in air at 24.3 c: 25.8,
24.6, 26.1, 22.9, 25.1, 27.3, 24.0, 24.5, 24.5, 23.9, 26.2, 24.3, 24.6, 23.3, 25.5, 28.1, 24.8, 23.5,
26.3, 25.4, 25.5, 23.9, 27.0, 24.8, 22.9, 25.4. Test if the twenty five body temperatures came
from a population whose mean is 24.3 C ( = 0.05)
2. Weight change of twelve rats after being subjected to a regime of forced exercise. Each weight
change ( in g ) is the weight after exercise minus the weight before.
1.7, 0.7, -0.4, -1.8, 0.2, 0.9, -1.2, -0.9, -1.8, -1.4, -1.8, -2.0
Test whether the exercise has significant weight loss ( = 0.05)
3. A consumer group is concerned with fat content of a certain grade of steakburger submit to an
independent laboratory a random samples of 12 steakburger for analysis. The percent of fat in
each steakburgers is as follows
21, 18, 19, 16, 18, 24, 22, 19, 24, 14, 18, 15
4. The manufacturer claims that the mean fat content of this grade is less than 20%. Assuming
that percentage fat content to be normally distributed with standard deviation of 3, carryout the
statistical hypothesis test in order to advise the consumer group as the validity of the
manufacturers claim
5. The data are weight changes of humans, tabulated after administration of a drug proposed to
result in weight loss. Each weight change (in kg) is the weight after minus weight before drug
administration ( = 0.05)
0.2, -0.5, -1.3, -1.6, -0.7, 0.4, -0.1, 0.0, -0.6, -0.6, -1.1, -1.2, -0.8
6. In processing grain in brewering industry, the percentage extract recovered is measured. A
particular brewing introduces a new source of grain, and percentage extract on 11 eleven
separate days as follows
95.2, 93.1, 93.5, 95.9, 94.0, 92.0, 94.4, 93.2, 95.5, 92.3, 95.4
Test the hypothesis that the true mean percentage extract recovered is 95.0 %. What assumption
you have made in carrying out your test?
