The number of comments per post on a social media site is exponentially distributed, with the average post receiving ten comments. What percentage of posts get fewer than three comments? More than 50? Between five and ten?
What will be an ideal response?
We find ? = 1 / 10 = .1, so that pr(X < x) = 1 - e^(-?x) = 1 - e^(-.1x)
Thus, the percentage of posts that get fewer than 3: pr(X < 3) = 1 - e^(-.1 * 3) = .259
More than 50: pr(X > 50) = 1 - pr(X < 50) = e^(-.1 * 50) = .007
Between 5 and 10: pr(X > 5) - pr(X > 10) = e^(-.1 * 5) - e^(-.1 * 10) = .607 - .368 = .239
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Foreign governments
A. often contribute large sums of money to key members of Congress. B. sometimes hire former members of Congress as lobbyists. C. provide expensive gifts to members of Congress who travel to a country on official government business. D. are rarely interested in the policy debates concerning trade issues. E. are prohibited by law from attempting to influence U.S. policy.
Which of the following established the Constitution of the European Union?
A) The Treaty of Nice B) The Treaty of Amsterdam C) The Lisbon Treaty D) The Maastricht Treaty
Through 2000, the Constitution had been amended twenty-seven times
Indicate whether the statement is true or false
What was the reason the Literary Digest incorrectly forecast the winner of the 1936 presidential election?
a. Quota sampling b. A biased sample c. Random sampling d. Exit polling