Please answer the following questions. Type your answer to each question in the box beneath the question.
If John can drink one barrel of water in 6 days, and Mary can drink one barrel of water in 12 days,
how many days would it take them to drink one barrel of water together?
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Jerry received both the 15th highest and the 15th lowest mark in the class.
How many students are in the class?
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A man buys a pig for $60, sells it for $70, buys it back for $80, and sells it finally for $90.
How many dollars has he made?
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Simon decided to invest $8,000 in the stock market one day early in 2008.
Six months after he invested, on July 17, the stocks he had purchased were down 50%.
Fortunately for Simon, from July 17 to October 17, the stocks he had purchased went up 75%.
As of October 17, Simon has:
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