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题目： 2x + y years ago, Roberto was 3x + y years old. How many years old was Roberto x years ago?

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题目： Each circle has center O. The radius of the smaller circle is 2 and the radius of the larger circle is 6. If a point is selected at random from the larger circular region, what is the probability that the point will lie in the shaded region?

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题目： If A is the initial amount put into an account, P is the annual percentage rate of interest, which remains fixed, and the account compounds quarterly, which of the following is an expression, in terms of A and P, for the amount in the account after 5 years?

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题目： If x and y are both positive then $$\sqrt{72x^{3}y^{16}}$$ =

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题目： If the mean of list A is 6.8 and the standard deviation is 3.6, then how many elements of list A are within 1 unit of standard deviation of the mean?A = {2, 9, 2, 6, 9, 10, 7, 4, 5, 14}

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题目： Kim is taking a math class, and the teacher gives a multiple choice test consisting of 8 questions. If each question has 5 answer choices, and Kim answers every question, in how many different ways can she complete the test?

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题目： In 2008, the total revenue from movies was 842.1 million dollars. If Rocky XII generated 4.2 million dollars in revenue, approximately what percent of the total revenue was generated by Rocky XII?

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题目： The probability that event A occurs is 0.4, and the probability that events A and B both occur is 0.25. If the probability that either event A or event B occurs is 0.6, what is the probability that event B will occur?

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题目： How many multiples of 5 are there between 81 and 358?

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题目： Rank those three in order from smallest to biggest.

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题目： 2 - [1 - (1 - [2 - 3] - 2) + 3] =

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题目： Which of the following sets of numbers has the greatest standard deviation?

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题目： Don has x marbles. If y marbles are white, what percent of Don's marbles are NOT white?

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题目： A retailer purchases shirts from a wholesaler and then sells the shirts in her store at a retail price that is 80 percent greater than the wholesale price. If the retailer decreases the retail price by 30 percent this will have the same effect as increasing the wholesale price by what percent?

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题目： If the average (arithmetic mean) of 24 consecutive odd integers is 48, what is the median of the 24 numbers?