Among fatal plane crashes that occurred during the past 60 years, 508 were due to piloterror, 81 were due to other humanerror, 333 were due toweather, 197 were due to mechanicalproblems, and 282 were due to sabotage.

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

Pilot error___%

Other human error. _%

Weather. %

Mechanical problems. %

Sabotage %