Answer: Crashes due to pilot error is the most serious threat to aviation safety as it has highest relative frequency.
Step-by-step explanation:
Since we have given that
Number of crashes due to pilot error = 699
Number of crashes due to other human error = 88
Number of crashes due to mechanical problems = 156
Number of crashes due to sabotage = 164
Total number of crashes = 699+88+156+164 = 1167
So, Relative frequency distribution :
Pilot error = [tex]\dfrac{699}{1167}\times 100=59.89\%[/tex]
Human error = [tex]\dfrac{88}{1167}\times 100=7.54\%[/tex]
Mechanical problems = [tex]\dfrac{156}{1167}\times 100=13.36\%[/tex]
Sabtoge = [tex]\dfrac{164}{1167}\times 100=14.05\%[/tex]
Crashes due to pilot error is the most serious threat to aviation safety as it has highest relative frequency.
