# sample distrbutions

• Feb 20th 2008, 02:33 PM
xfyz
sample distrbutions
The assembly line that produces components of a missile system has historically resulted in 2% defective rate. A random sample of 800 components is drawn. What is the probability that the defective rate is greater than 4%?

can someone help me with this? thank you
• Feb 20th 2008, 03:13 PM
CaptainBlack
Quote:

Originally Posted by xfyz
The assembly line that produces components of a missile system has historically resulted in 2% defective rate. A random sample of 800 components is drawn. What is the probability that the defective rate is greater than 4%?

can someone help me with this? thank you

The actual number of defectives in the batch has a binomial distribution $B(0.02,800)$, and you are asked for $p(n>32)$ where $n$ is the number of defectives in the batch.

Now how we proceed depends on what you were doing when this question was set. I guess you are supposed to used the Poisson approximation to the binomial for this.

RonL