#7

Among fatal plane crashes that occurred during the past 70 years, 396 were due to piloterror, 67 were due to other humanerror, 623 were due toweather, 142 were due to mechanicalproblems, and 437 were due to sabotage.

Construct the relative frequency distribution. What is the most serious threat to aviationsafety, and can anything be done aboutit?

Complete the relative frequency distribution below.

Cause Relative Frequency

Pilot error __________%

Other human error __________%

Weather ___________%

Mechanical problems ________%

Sabotage __________%

(Round to one decimal place asneeded.)

What is the most serious threat to aviationsafety, and can anything be done aboutit?

A.

Piloterroris the most serious threat to aviation safety. Pilots could be better trained.

B.

Weatheris the most serious threat to aviation safety. Weather monitoring systems could be improved.

C.

Sabotageis the most serious threat to aviation safety. Airport security could be increased.

D.

Mechanicalproblemsare the most serious threat to aviation safety. New planes could be better

#13

Below are the jersey numbers of 11 players randomly selected from a football team. Find therange, variance, and standard deviation for the given sample data. What do the results tellus?

705567113392643867131

Range=________ (Round to one decimal place asneeded.)

Sample standard deviation=_________ (Round to one decimal place asneeded.)

Sample variance= __________ (Round to one decimal place asneeded.)

What do the results tellus?

A.

Jersey numbers on a football team do not vary as much as expected.

B.

Jersey numbers are nominal data that are just replacements fornames, so the resulting statistics are meaningless.

C.

The sample standard deviation is too large in comparison to the range.

D.

Jersey numbers on a football team vary much more than expected.