# Statistics

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A construction company builds apartment buildings. The construction time follows a normal distribution with a mean time of 200 days and a standard diviation of 20 days. (a) What is the probability of completing a building in 224 days or less? (b) What is the probability that it will take between 210 and 224 days to complete a building?

• Statistics -

Z = (score-mean)/SD

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportions related to the Z scores.

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