Homework Help: Math Help Please!!!!

Posted by Taylor on Saturday, February 23, 2013 at 8:39pm.

The breaking strengths (say, y) for one foot square samples of a particular synthetic fabric are approximately normally distributed with a mean of 2280 pounds per square inch and a standard deviation of 10.6 psi.

a) find the probability of selecting a 1 foot square sample of material at random that on testing would have a breaking strength in excess of 2240 psi.

b)what is the breaking strength value in psi that separates the strongest 20% of one foot square samples from the weakest 80%?

Math Help Please!!!! - PsyDAG, Sunday, February 24, 2013 at 11:38am
a) Z = (score-mean)/SD

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability related to the Z score.

b) Start with Z value for .20 and insert i8n equation above.

Answer this Question

Related Questions

Math - adam has 2 yards of fabric to make a shirt. He needs 1 foot of fabric for...
Math - Lisa bought two equal pieces of fabric. She will cut squares for a quilt ...
math - jodys has a rectangular piece of fabric 7/8 yard long and 4/5 yard wide. ...
math - jodys has a rectangular piece of fabric 7/8 yard long and 4/5 yard wide. ...
math - The home economics team has 6 3/4 feet of fabric for a class project. ...
math - how many square inches are in a square foot A square foot has 12 inches ...
Math - A quilter has 6 yards of fabric that is 54 inches wide. The fabric weighs...
statistics - 8. Suppose that the IQ score for a person selected from a certain ...
math - How many square inches are needed to cover a square foot? My Dad and I ...
Math - Ms.Daza bought 3 1/2 yards of fabric. She used 2/3 of the fabric to make ...

For Further Reading

First Name:
School Subject:
Answer: