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题目内容
1, 2, 2, 3, 3, 3, 4, 4, 4, 4, ......, 24

The list above consists of 300 entries that are integers in increasing order, and each integer n occurs n times for 1 ≤ n ≤ 24. What is the least integer k in the list for which at least 15% of all the entries are less than k?
On October 1, 2006, at a certain elementary school, the ratio of the number of students to the number of teachers was 34 to 1. By October 1, 2007, the number of students had increased by 5 percent and the number of teachers had increased by 2 percent from the previous year. What was the ratio of the number of students to the number of teachers at the school on October 1, 2007 ?
The probability distribution function P of a continuous random variable X is defined as shown. If P(X≤k) < $$\frac{1}{2}$$ , which of the following could be the value of k?



Indicate all such values.
For each value $$x$$ in a list of values with mean $$m$$, the absolute deviation of $$x$$ from the mean is defined as $$|x-m|$$.

List W consists of 5 values, all of which are positive integers. The least value in W is 1 and the greatest value in W is 10.

Quantity A

The range of the absolute deviations of the values in W from the mean

Quantity B

5




Quantity A

$$x$$

Quantity B

$$y$$


Five lists of data with 20 data values in each have arithmetic means $$a_1, a_2, a_3, a_4$$, and $$a_5$$ and medians $$m_1, m_2, m_3, m_4$$, and $$m_5$$,respectively.

Quantity A

The median of $$a_1, a_2, a_3, a_4$$, and $$a_5$$

Quantity B

The arithmetic mean of $$m_1, m_2, m_3, m_4$$, and $$m_5$$


$$x$$ and $$y$$ are prime numbers such that $$x + y = 43$$.

Quantity A

$$xy$$

Quantity B

$$86$$


z=x+2y, where x and y are integers; 30 ≤ x ≤ 39; and 20 ≤ y ≤ 29.

Quantity A

The number of possible values that could be the tens digit of z

Quantity B

4








Points I, J, S, T, and U lie on line $$k_1$$ and points H, K, and R lie on line $$k_2$$, Where $$k_1$$ and $$k_2$$ are parallel. Line segments HK and ST have equal length, and line segments IJ and TU have equal length.

Quantity A

The area of trapezoidal region HIJK

Quantity B

The area of triangular region RSU


On the first day of a sale, a storekeeper sold $$\frac{3}{5}$$ of the goods in the initial inventory. On the second day of the sale, the storekeeper sold $$\frac{1}{4}$$ of the goods that remained at the end of the first day of the sale.

Quantity A

The fraction of the goods in the initial inventory that remained at the end of the second day of the sale

Quantity B

$$\frac{3}{10}$$


a ≠ 0

Quantity A

$$a^{2}-a$$

Quantity B

$$a-a^{2}$$


$$\frac{1}{x}-\frac{1}{y}=\frac{1}{xy}$$ and xy ≠ 0.

Quantity A

x

Quantity B

y


A number is to be chosen at random from the integers from 1 to 100, inclusive. What is the probability that the number chosen will be an even integer greater than 90?
What is the y-intercept of the line in the xy-plane that passes through the point (1, 2) and is parallel to the line y+2x=1?
How many whole numbers between 10 and 43 have a remainder of 5 when divided by 7?
Starting from rest, a certain car travels a distance of Q meters in t seconds, where $$Q=4t^{2}$$ and 0≤ Q ≤ 64. In how many seconds does the car travel 64 meters, starting from rest?

_____seconds
If the annual commercial energy usage for lighting is $$w$$ units of energy, which of the following is closest to the annual commercial energy usage for refrigeration, in the same units of energy?
The ratio of the total annual residential energy usage to the total annual commercial energy usage is $$x$$ to $$y$$. Which of the following represents the fraction of the total annual energy usage, both residential and commercial, that is for lighting?
The annual commercial energy usage for space cooling is approximately what percent less than the annual commercial energy usage for space heating?

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