40 short answer and multiple choice questions.
kcndel
Questions10-20.docx
Question 10
Question 11
Question 12
Question 13
Question 14 a,b,c,d
In a Gallup poll of 1 comma 0011,001 randomly selected American sportsmenAmerican sportsmen, 89% said that cloning of humans should not be allowed.
Identify the sample, population, and sampling method. Then comment on whether you think it is likely that the sample is representative of the population. Identify the sample. Choose the correct answer below. A. all American sportsmenAmerican sportsmen B. 89% of randomly selected American sportsmenAmerican sportsmen C. the 1 comma 0011,001 randomly selected American sportsmenAmerican sportsmen D. sportsmensportsmen of the whole world Identify the population. Choose the correct answer below. A. the 1 comma 0011,001 randomly selected American sportsmenAmerican sportsmen B. all American sportsmenAmerican sportsmen C. sportsmensportsmen of the whole world D. 89% of randomly selected American sportsmenAmerican sportsmen Identify the sampling method. Choose the correct answer below.
A. Convenience B. Random C. Systematic Comment on whether you think it is likely that the sample is representative of the population. Choose the correct answer below. A. The size of the sample is not equal to the size of the population, so the sample is likely to be representative of the population. B. The sample is fairly large and random. Assuming it was obtained by a reputable firm, the sample is likely to be representative of the population. C. The members of the sample have different characteristics than members of the population, so the sample is not likely to be representative of the population.
Question 15
Question 16
Twenty-five people, consisting of a statistics professor and her students, are to measure the length of a room to the nearest tenth of a millimeter. Assume that everyone uses the same well-calibrated measuring device, such as a tape measure.
Complete parts a through d below.
a. All 25 measurements are not likely to be exactly the same; thus, the measurements will contain some sources of error. Are these errors systematic or random? Explain.
A.
These errors are random. If they were systematic, there would be a tendency for the measurements to be all too high or all too low.
B.
These errors are systematic, because it is undeterminable whether the measurements are too high or too low.
C.
These errors are systematic. If they were random, it would be undeterminable whether the measurements are all too high or too low.
D.
These errors are random, because there is a tendency for the measurements to be all too high or too low.
b. If the professor wants to minimize the effect of random errors in determining the length of the room, is it better to report her own personal measurement as the length of the room or to report the average of all 25 measurements? Explain.
A.
It is better to use the professor's own personal measurement because she has a more precise tape measure than her students.
B.
It is better to use the professor's own personal measurement because the random errors in the individual measurements will be multiplied in size 25 times in the average.
C.
It is better to use the average because it is likely to be in error by less than most of the individual measurements and it is more reliable than any single measurement.
D.
It is better to use the average because the average of many measurements is always equal to the true value.
c. Describe any possible sources of systematic errors in the measurement of the room length.
A.
Systematic errors might result if the tape measure is not long enough, and the students need to sum the measurements from the walls to some central point in the room.
B.
Systematic errors might result if the students rush, and do not make the measurements carefully.
C.
Systematic errors might result if the tape measure has a manufacturing defect that made all of the units too small on the tape.
D.
Systematic errors might result if there isn't much light in the room and the professor and students misread the tape measure.
d. Can the process of averaging all 25 measurements help reduce any systematic errors? Why or why not?
A.
No, because measurements that have systematic errors cannot be averaged.
B.
No, because if there is a systematic error in the measurements, that same error will be present in the average.
C.
Yes, because the average of many measurements is always equal to the true value.
D.
Yes, because the systematic errors will cancel out in the average.
Question 17
Question 18
The accompanying histogram shows the time until failure for a sample of
131131
computer chips. Classify the distribution according to its number of modes and its symmetry or skewness. In words, summarize the meaning of your results.
Classify the distribution. Choose the correct answer below.
A.
The distribution
is trimodalis trimodal
and
left dash skewedleft-skewed.
B.
The distribution
is unimodalis unimodal
and
left dash skewedleft-skewed.
C.
The distribution
is bimodalis bimodal
and
right dash skewedright-skewed.
D.
The distribution
is bimodalis bimodal
and
left dash skewedleft-skewed.
E.
The distribution
is unimodalis unimodal
and
right dash skewedright-skewed.
F.
The distribution
is trimodalis trimodal
and
right dash skewedright-skewed.
Summarize the meaning of the results. Choose the correct answer below.
A.
Most computer chips fail in the
first comma third comma and ninthfirst, third, and ninth
months of operation, and
decreasingdecreasing
numbers of chips fail as the months progress.
B.
Most computer chips fail in the
third and twelfththird and twelfth
months of operation, and
increasingincreasing
numbers of chips fail as the months progress.
C.
Most computer chips fail in the
twelfthtwelfth
month of operation, and
increasingincreasing
numbers of chips fail in the months leading up to that point.fail in the months leading up to that point.
D.
Most computer chips fail in the
firstfirst
month of operation, and
decreasingdecreasing
numbers of chips continue functioning in the following months.continue functioning in the following months.
Question 19
Question 20
