Historically 26% of students fail MATH2124. Assume that the
current class of 175 students forms a random sample.
What is the expected number of students who fail and the
variance of the number of students who fail?
Your answers can be rounded to four decimal digit accuracy when
entered.
E(fail) = | ||
Var(fail) = |
Historically 26% of students fail MATH2124. Assume that the current class of 175 students forms a...
The desired percentage of Silicon Dioxide (SiO2) in a certain type of aluminous cement is 5.3. Historically the percentage of Sio2 in the cement is normally distributed with a standard deviation of 0.32. To monitor this process, periodically an engineer takes a random sample of 9 measurements. A recent sample yielded a sample mean of 5.481 Find the p-value associated with the following hypothesis test. Ho:H 5.3 versus Ha: 5.3 Your answer can be rounded to four decimal digit accuracy...
The target diameter of bolts from a production line is 8mm.
Historically the bolt diameters are normally distributed with a
standard deviation of 0.05mm. To monitor this process periodically
an engineer takes a random sample of 4 measurements. Let µ be the
true average bolt diameter.
The rejection region is:
Find the minimum value of c that yields a test
with significance 0.05?
zα
1.282
1.645
1.960
2.326
2.576
3.090
α(tail area)
0.1
0.05
0.025
0.01
0.005
0.001
%ile...
The target diameter of bolts from a production line is 12mm. Historically the bolt diameters are normally distributed with a standard deviation of 0.1mm. To monitor this process periodically an engineer takes a random sample of 5 measurements. Let µ be the true average bolt diameter. The rejection region is: Find the minimum value of c that yields a test with significance 0.01? zα 1.282 1.645 1.960 2.326 2.576 3.090 α(tail area) 0.1 0.05 0.025 0.01 0.005 0.001 %ile 90...
Find the expected value and the standard deviation for the discrete random variable: y -2 -1 0 1 2 Pr(Y = y) 0.31 0.18 0.17 0.26 …… Your answers can be rounded to four decimal digit accuracy when entered. E(Y) = SD(Y) =
Q1.
Q2.
Uhom a tion of 0.305. To monitor this Question 13 (1 mark) Attempt 1 The desired percentage of Silicon Dioxide (SiO2) in a certain type of aluminous cement is 5.4. Historically the percentage of SiO2 in the cement is normally distributed w process, periodically an engineer takes a random sample of 16 measurements. A recent sample yielded a sample mean of 5.228 Find the p-value associated with the following hypothesis test. Ho:u=5.4 versus H,: *5.4 Your answer can...
Suppose that n students are selected at random without replacement from a class containing 28 students, of whom 8 are boys and 20 are girls. We assume that 0 < n < 28. Let X denote the number of boys that are obtained. Answer the following questions: a (4 marks) State the distribution of X, with parameters b (1 mark) Write down the possible values of X c (1 mark) Express E(X) in terms of n. d (4 marks) For...
The target diameter of bolts from a production line is 10mm. Historically the bolt diameters are normally distributed with a standard deviation of 0.15mm. To monitor this process periodically an engineer takes a random sample of 6 measurements. Let µ be the true average bolt diameter. The rejection region is: Find the minimum value of c that yields a test with significance 0.01? zα 1.282 1.645 1.960 2.326 2.576 3.090 α(tail area) 0.1 0.05 0.025 0.01 0.005 0.001 %ile...
Question 13 (1 mark) Attempt 6 The calibration of a scale is to be checked by weighing a 30kg test specimen. A random sample of 16 measurements yielded a sample standard deviation of 0.19 kg and sample mean 29.91 kg Assuming the central limit theorem applies and s o, find the p-value associated with the following hypothesis test. Ho H 30 versus Ha: u 30 Your answer can be rounded to four decimal digit accuracy when entered. p-value-
Question 13...
Engineers at a distribution company believe that the average number of damaged packages shipped by air freight do not exceed 11% To test the hypothesis Ho: Pe=0.11 versus H P >0.11 a random sample of 190 packages shipped by air freight are sampled, and 28 are found to be damaged. Find the large sample p-value associated with the hypothesis test. Your answer can be rounded to four decimal digit accuracy when entered. D-value Skipped
Students in a statistics class are conducting a survey to estimate the mean pe numbers in the bones. number of units students at their college are enrolled in. The students collect a part es points random sample of 47 students. The mean of the sample is 12.3 units. The Part 2: 5 points sample has a standard deviation of 1.9 units. 20 points What is the 95% confidence interval for the average number of units that students in their college...