Based on data from the 2010 Census the average age of a Pierce County, Washington

Based on data from the 2010 Census the average age of a Pierce County, Washington resident is 41 years with a standard deviation of 12.3 . The data is normally distributed.
The median age, in years, is:
Suppose that the distribution of fly balls hit to the outfield (in baseball) is normally distributed with a mean of 250 feet and a standard deviation of 50 feet. We randomly sample 49 fly balls.
Find the 60th percentile of the distribution of the average of fly balls
Suppose that the distribution of fly balls hit to the outfield (in baseball) is normally distributed with a mean of 250 feet and a standard deviation of 50 feet. We randomly sample 49 fly balls.
What is the probability that the 49 fly balls traveled an average of less than 240 feet?
A radio news story claimed that half of all U.S. adults have Internet access. In a national poll about Internet usage (The Pew Internet Project), 12,638 U.S. adults were surveyed and it was found that 6413 of those surveyed had Internet access. At a 5% level of significance, perform a hypothesis test to test the claim made by the radio news story.
The correct conclusion is:

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Solution: Based on data from the 2010 Census the average age of a Pierce County, Washington