statistics
posted by Anonymous .
Solve the problem. The lifetime of a new brand of light bulb can be described by a Normal model with a mean of 2000 hours and a standard deviation of 250 hours. Find the percentage of light bulbs that will last more than 2600 hours.
A.) 100%
B.) 5%
C.) 99.18%
D.) 0.82%
E.) Cannot be determined

statistics 
PsyDAG
Z = (scoremean)/SD
Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion related to that Z score.
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