Thursday

August 21, 2014

August 21, 2014

Posted by **kevin** on Thursday, April 25, 2013 at 1:42pm.

a) What is the probability that a single car, selected at random,

will take between 28 and 34 hours?

b) What is the probability that the mean of the times for a sample

of 25 cars will be between 28 and 34 hours?

- statistics -
**PsyDAG**, Friday, April 26, 2013 at 3:24pma) Z = (score-mean)/SD

Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability related to the Z score.

b) Z = (score-mean)/SEm

SEm = SD/√n

Use the table.

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