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题目： Lindsay can paint $$\frac{1}{x}$$ of a certain room in one hour. If Lindsay and Joseph, working together at their respective rates, can paint the room in one hour, what fraction of the room can Joseph paint in 20 minutes?

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题目： If x + y = 3, and $$x^{2} – y^{2} = 12$$, what is the value of x – y?

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题目： Which of the following is the second greatest?

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题目： If $$x^{2} – 4x = 5$$, then one possible value of x – 4 =

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题目： Two circles share a center at point C, as shown to the right. Segment AC is broken up into two shorter segments, AB and BC, with dimensions shown. What is the ratio of the area of the large circle to the area of the small circle ?

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题目： Two buses and a van were employed to transport a class of students on a field trip. $$\frac{3}{5}$$ of the class boarded the first bus. $$\frac{2}{3}$$ of the remaining students boarded the second bus, and the rest of the students boarded the van. When the second bus broke down,$$\frac{ 1}{2}$$ of the students on the second bus boarded the first bus. What fraction of the class was on board the first bus?

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题目： If a and b are positive integers and$$ x = 4^{ a} and y = 9^{ b}$$, which of the following is a possible units digit of xy?

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题目： When a is divided by b, the quotient is c and the remainder is d. Which of the following expressions is equal to d?

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题目： If$$ 9^{2x + 1} = 27^{2}$$, then x =

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题目： Barry walks from one end to the other of a 30-meter long moving walkway at a constant rate in 30 seconds, assisted by the walkway. When he reaches the end, he reverses direction and continues walking with the same speed, but this time it takes him 120 seconds because he is traveling against the direction of the moving walkway. If the walkway were to stop moving, how many seconds would it take Barry to walk from one end of the walkway to the other?

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题目： The 7th grade French and Spanish classes each have 15 students in them, and there are five students in the 7th grade taking both languages. If everyone in the 7th grade is in at least one of the two language classes, how many students are taking just one of the two classes?

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题目： Given that a is the average (arithmetic mean) of the first nine positive multiples of six and b is the median of the first twelve positive multiples of six, what is the ratio of a to b?

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题目： If the largest single-digit prime number is raised to the exponent equal to the number of its positive factors, what is the result?

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题目： A data set with a mean of 60 has a standard deviation of 3.5. Which of the following is the smallest number that falls within one standard deviation of the mean?

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题目： Set A contains three different positive odd integers and two different positive even integers; set B contains two different positive odd integers and three different positive even integers. If one integer from set A and one integer from set B are chosen at random, what is the probability that the product of the chosen integers is even?