Among fatal plane crashes that occurred during the past 65 years, 627 were due to pilot error, 64 were due to other human error, 113 were due to weather, 382 were due to mechanical problems, and 481 were due to sabotage. Construct the relative frequency distribution. What is the most serious threat to aviation safety, and can anything be done about it?
A. Sabotage is the most serious threat to aviation safety. Airport security could be increased.
B. Mechanical problems are the most serious threat to aviation safety. New planes could be better engineered.
C. Weather is the most serious threat to aviation safety. Weather monitoring systems could be improved.
D. Pilot error isPilot error is the most serious threat to aviation safety. Pilots could be better trained.

D. Pilot error isPilot error is the most serious threat to aviation safety. Pilots could be better trained.

Step-by-step explanation:

We can construct the relative frequency distribution dividing the amount of incidents for each category by the total amount of incidents.

This amount is:

Then, the relative frequency for each category is:

As the pilot error has the largest relative frequency, we can conclude that pilot error is the most serious threat to aviation safety.

first anwser choice.

step-by-step explanation:

the greater/less or equal to symbol (> or < with the line at the bottom) is a closed/filled in circle.

-5c + 2 _< _27

subtract from both sides by 2

-5c _< _ 27

divide both sides by -5

c _< _ 5.4

flip the inequality sign

c _> _5.4

the only possible answer that would match the simplified inequality is the first answer choice