Posted by Mike on Saturday, March 12, 2011 at 1:29pm.
I need help with this problem for school. For the first one i got .3758 and second 1.6, but i don't think they are right. My calculations are off
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?
0.6242
0.3758
0.8926
0.2684
0.1074
What is the expected number of policies having emergency road service?
3.5
8.0
1.6
2.0
5.0

Statistics Help  MathGuru, Wednesday, March 16, 2011 at 9:09pm
You need to find P(0). Use a binomial probability table, with x = 0, n = 10, and p = .2. Subtract the value you find in the table from 1. This will be your probability.
Second part: take n * p, where n = 10, and p = .2.
I hope this will help.