An investigator polls a representative sample of common cold sufferers, asking them to estimate the number of hours of physical discomfort caused by their most recent cold. Their estimates approximate a normal curve with a mean of 83 hours and a standard deviation of 20 hour.

6. What percentage of sufferers estimate that their colds lasted for longer than forty-eight hours?

- What percentage suffered for fewer than 61 hours?
- What percentage suffered for between one and three days?
- Inverse Normal Distribution: What is the estimated number of hours for the shortest-suffering 10 percent?
- Inverse Normal Distribution: A medical researcher wishes to concentrate on the 20 percent who suffered the most. She will work only with those who estimate that they suffered for more than _____hours.

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What percentage of sufferers estimate that their colds lasted for longer than forty-eight hours? Z = (48-83)/20 = = P(z =... View the full answer