The average playing time of compact discs in a large collectionis 35 minutes, and the standard deviation is 3 minutes.
(a) What value is 1 standard deviation above the mean? 1standard deviation below the mean? What values are 2 standarddeviations away from the mean?
1 standard deviation above themean | |
1 standard deviation below themean | |
2 standard deviations above themean | |
2 standard deviations below themean    | |
b) Without assuming anything about the distribution of times, atleast what percentage of the times are between 29 and 41 minutes?(Round the answer to the nearest whole number.)
At least   %
(c) Without assuming anything about the distribution of times, whatcan be said about the percentage of times that are either less than26 minutes or greater than 44 minutes? (Round the answer to thenearest whole number.)
No more than   %
(d) Assuming that the distribution of times is normal, about whatpercentage of times are between 29 and 41 minutes? (Round theanswers to two decimal places, if needed.)
  %
Less than 26 min or greater than 44 min?
  %
Less than 26 min?
  %