SOLUTION: 1. 10 % of article made by a company are defective, if 5 article are selected at random, what is the probability that (i)3 are defective. (ii) less than 2 are defective. (iii) more

Algebra ->  Probability-and-statistics -> SOLUTION: 1. 10 % of article made by a company are defective, if 5 article are selected at random, what is the probability that (i)3 are defective. (ii) less than 2 are defective. (iii) more      Log On


   



Question 983415: 1. 10 % of article made by a company are defective, if 5 article are selected at random, what is the probability that (i)3 are defective. (ii) less than 2 are defective. (iii) more than 2 are defective.


Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
First is 5C3*(0.1)^3(0.9)^2; number of ways 3 can be defective out of 5 times the probability is 0.0081 (0.01*0.81)
Fewer than 2 means 1 or 0 are defective
P(1)=5C1(0.1)^1(0.9^4)=0.328
P(0)=(.9^5)=0.590
The probability fewer than 2 are defective is 0.918. That makes sense since it is a low probability to find one defective.
Probability of 2 defective is 5C2(0.1^2)(0.9^3)=0.073
The probability of 2 or fewer defective (using the above) is 0.918+0.073=0.991.
Therefore, the complement is greater than 2 are defective, which is 0.009.