Answer: 54% or 0.54
Step-by-step explanation:
The probability that the person is travelling on business is the expected value of the various probabilities that they are travelling on business.
= (Percentage using major airlines * percentage using major airlines to travel for business) + (Percentage using private * percentage using private airlines to travel for business) + (Percentage using commercial * percentage using commercial airlines to travel for business)
= (60% * 40%) + (20% * 70%) + ( (100% - 60% - 20%) * 80%)
= 24% + 14% + 16%
= 54%