It is known that about 20% of car insurance policies include emergency road service. Suppose we randomly select 10 car insurance policies.
What is the probability that at least one policy will have emergency road service?
Answer
0.6242
0.3758
0.8926
0.2684
0.1074
What is the expected number of policies having emergency road service?
Answer
3.5
8.0
1.6
2.0
5.0
I couldn't figure out the second part. for the first one i got .3758
2 answers
Please type your subject in the School Subject box. Any other words, including obscure abbreviations, are likely to delay responses from a teacher who knows that subject well.
How did you get 0.3748 for part 1? The correct answer is 1 - (0.8)^10
One minus the probability that none of the ten have roadside coverage
The expecation value is the single-policy probabiity x (number of policies). That product is 2.
One minus the probability that none of the ten have roadside coverage
The expecation value is the single-policy probabiity x (number of policies). That product is 2.