Homework Help: MATH

Posted by Ty on Thursday, April 1, 2010 at 11:01am.

Battery Power Problem. A certain type of thermal battery
for an airplane navigation device backup power has a
mean life of 300 hours with a standard deviation of 15
hours. What proportion of these batteries can be
expected to have lives of 322 hours or less? Assume a normal
distribution of backup power device lives.

MATH - PsyDAG, Friday, April 2, 2010 at 11:08am
Z = (x - mean)/SD = (322-300)/15

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion below the Z score found from above.

Answer this Question

Related Questions

Help Math! - Battery Power Problem. A certain type of thermal battery for an ...
Teacher Math - Battery Power Problem. A certain type of thermal battery for an ...
MATH Prob. - Battery Power Problem. A certain type of thermal battery for an ...
Math - A certain type of thermal battery for an airplane navigation device ...
Math - A certain type of thermal battery for an airplane navigation device ...
Statistics - The lifetime of a certain smart phone battery has an unknown ...
Statistics - The lifetime of a certain smart phone battery has an unknown ...
Physics - A battery delivering a current of 55.0 A to a circuit has a terminal ...
Physics - A battery charger is connected to a dead battery and delivers a ...
statistics - The life span of the battery pack is known to be Normally ...

For Further Reading

First Name:
School Subject:
Answer: