# mean and standard deviation help please!

• Nov 25th 2008, 01:11 PM
mercury228
mean and standard deviation help please!
I have a question here that I cannot figure out (actually a few). I am not to good at this, and need some one to help me out. If you can help on this one maybe I can figure out the rest.

The weight of potato chip bags filled by a machine at a packing plant is normally distributed with a mean of 15.0 ounces and a standard deviation of 0.2 ounces. What is the probability that a randomly chosen bag will weigh more than 15.6 ounces?
• Nov 25th 2008, 08:18 PM
mr fantastic
Quote:

Originally Posted by mercury228
I have a question here that I cannot figure out (actually a few). I am not to good at this, and need some one to help me out. If you can help on this one maybe I can figure out the rest.

The weight of potato chip bags filled by a machine at a packing plant is normally distributed with a mean of 15.0 ounces and a standard deviation of 0.2 ounces. What is the probability that a randomly chosen bag will weigh more than 15.6 ounces?

$\Pr(X > 15.6) = \Pr\left(Z > \frac{15.6 - 15.0}{0.2}\right) = \Pr(Z > 3) = 1 - \Pr(Z < 3)$.

Use your Standard Normal Distribution Tables to finish the calculation.