SOLUTION: A new type of light bulb has an average lifespan of 1200 hours with a standard deviation of 75 hours. Use the table to find the probability that a light bulb chosen at random will

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Question 870611: A new type of light bulb has an average lifespan of 1200 hours with a standard deviation of 75 hours. Use the table to find the probability that a light bulb chosen at random will last more than 1155 hours. 
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
mean = 1200, SD 75
P(x > 1155), z = -45/75 = -.6
P(z < -.6) = 27.43%
Use table or Calculator; normalcdf(-10, -.6)) | -10 a placeholder