Math
posted by angela
If light bulbs have lives that are normally distributed with a mean of
2500 hours and a standard deviation of 500 hours, what percentage of
light bulbs have a life less than 2500 hours?
A. About 25%
B. About 50%
C. About 75%
D. About 68%
Answer B

PsyDAG
Please only post your questions once. Repeating posts will not get a quicker response. In addition, it wastes our time looking over reposts that have already been answered in another post. Thank you.
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