SOLUTION: The average playing time of compact discs in a large collection is 35 min, and the standard deviation is 4 min. 1.)Assuming that the distribution of times is normal, approximately

Question 508859: The average playing time of compact discs in a large collection is 35 min, and the standard deviation is 4 min.
1.)Assuming that the distribution of times is normal, approximately what percentage of times are between 27 and 43 min? (Round the answers to two decimal places, if needed.)
2.)Less than 23 min or greater than 47 min?
3.)Less than 23 min?
Answer by edjones(8007) (Show Source): You can put this solution on YOUR website!
1)
z=(27-35)/4=-2
z=(43-35)/4=2
Area under normal curve between -2 an 2 is .95
.
Ed
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