For the following situation, which type of test would you run ( use letter from
ID: 3264469 • Letter: F
Question
For the following situation, which type of test would you run ( use letter from problem 8) and state the Ho and H1
a) An engineer is concerned that the hardness of subcritically annealed ductile iron is higher than the standard 170 so she measures the Brinell hardness of a random sample of 25 pieces.
b) A manufacturer claims that the thickness of the spearmint gum it produces is 7.5 one-hundredths of an inch. A quality control specialist regularly checks this claim. On one production run, he took a random sample of n = 10 pieces of gum and measured their thickness.
c) To test if newborn babies are more likely to be boys than girls. A random sample found 13,173 boys were born among 25,468 newborn children. The sample proportion of boys was 0.5172. Is there evidence that the birth of boys is more common than the birth of girls in the entire population?
d) The table below contains the historical distribution and current distribution of the race of students at a college. The college put a strong effort into recruiting a more diverse group of students. They would like to know if the distribution is statistically different this year than in the past.
Caucasian
African American
Hispanic
Asian
Alaskan
Mixed/other
Historical
60
15
5
18
0
2
This year
50
17
08
23
1
1
e) Males and females were asked about what they would do if they received a $100 bill by mail, addressed to their neighbor, but wrongly delivered to them. Would they return it to their neighbor? Of the 69 males sampled, 52 said yes and of the 131 females sampled, 120 yes.
f) You are testing a treatment for diabetes and you suspect it will impact men and women differently. You design a test in which you record blood sugar before taking the medicine and after.
g) You are having a debate with your roommate on who sleeps more male or female students. You randomly survey 20 males and 20 females and ask them how many hours they sleep a night.
h) A biologist was interested in determining whether sunflower seedlings treated with an extract from Vinca minor roots resulted in a lower average height of sunflower seedlings than the standard height of 15.7 cm. The biologist treated a random sample of n = 33 seedlings with the extract .
i) You suspect night shift is more productive than day shift. You pull production reports for 20 random shifts.
j) You want to test if the amount of vitamin C in an orange varies by more than the amount of vitamin C in a grapefruit.
Caucasian
African American
Hispanic
Asian
Alaskan
Mixed/other
Historical
60
15
5
18
0
2
This year
50
17
08
23
1
1
Explanation / Answer
a) An engineer is concerned that the hardness of subcritically annealed ductile iron is higher than the standard 170 so she measures the Brinell hardness of a random sample of 25 pieces.
Ans: Here, one-samplet-test (Right-tailed test) will be used.
H0:= 170
HA:> 170
b) Here, one-samplet-test (two-tailed test) will be used.
H0:= 7.5
HA: 7.5
c) Here, we want to test
H0:p=0.5
HA:p>0.5
This is a one sample proportion test (right tailed).
d) paired sample t test (two tailed) can be used here.
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.