# Answer on Statistics and Probability Question for susan

Question #3946

A GE light bulb is supposed to last for 1200 hours. In fact, light bulbs of this type last only 1185 hours with a standard deviation of 70 hours. What is the probability that a sample of 100 light bulbs will have an average life of at least 1200 hours?

Expert's answer

Need a fast expert's response?

Submit orderand get a quick answer at the best price

for any assignment or question with DETAILED EXPLANATIONS!

## Comments

Assignment Expert21.03.2016 12:08Z is equal to the standardized variable of the average life. In other words, Z is calculated as follows: the average life minus the sample mean of the average life and the result is finally divided by the standard deviation of the average life.

Ella21.03.2016 10:26How do we find what z is?

## Leave a comment