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If a family were selected at random from the survey sample, what is the probability that the family would own more than 2 motor vehicles?
Each digit of a 20-digit number is either a 1, 2, 3, 4, or 5. If the average (arithmetic mean) of 15 of the 20 digits of the number is 2.8 and if M is the average of all 20 digits of the number, then M must satisfy which of the following inequalities?

Quantity A

The average (arithmetic mean) of the integers from 1 to 31, inclusive

Quantity B

16


Stores A, B, C, and D sell a certain model of printer for the same retail price. The retail price of the printer is discounted by 10 percent, 20 percent, 16 percent, and 12 percent at Stores A, B, C, and D, respectively. If the retail price of the printer is at least $100, which of the following statements about the discounted prices at the four stores must be true?

Indicate all such statements.
The standard deviation of n numbers $$x_{1}$$, $$x_{2}$$, $$x_{3}$$,......, $$x_{n}$$, with mean $$\overline{x}$$ is equal to $$\sqrt{\frac{s}{n}}$$, where S is the sum of the squared differences $$(x_{i} - \overline{x})^{2}$$ for 1 ≤ i ≤ n.

If the standard deviation of the 5 numbers 20-2c, 20-c, 20, 20+c, and 20+2c is greater than 6, which of the following could be the value of c?

Indicate all such values.
In the xy-plane, 8 data points lie on the line with equation y=40+5x. If the standard deviation of the x-coordinates of the 8 points is 4.6, what is the standard deviation of the y-coordinates of the 8 points?


The figure shows a normal distribution with mean m and standard deviation d, including approximate percents of the distribution corresponding to the six regions shown.

The random variable Y is normally distributed with mean 576. If the value 628 is at the $$84^{th}$$ percentile of the distribution of Y, which of the following is the best estimate of the value at the $$98^{th}$$ percentile of the distribution of Y?


If 30 percent of the people surveyed use both of the methods "exercise near home or work" and "exercise outdoors", what percent of people surveyed use at least one of the two methods?
The sum of the first n positive integers can be found using the formula $$\frac{n(n+1)}{2}$$.

The sum of the first n positive odd integers can be found using the formula $$(\frac{s}{2})^2$$, where s is the sum of the first and last odd integer.

If x is equal to the sum of the integers from 1 to 100, and if y is equal to $$\frac{1}{2}$$ of the sum of the odd integers from 1 to 199, what is the value of x-y?
$$C_1$$, $$C_2$$, $$C_3$$, ......,$$C_K$$, ......

The sequence shown above is defined by $$C_1$$=7 and $$C_{K+1}$$= $$\frac{1}{7}$$ $$C_K$$, for each positive integer k

Quantity A

$$C_{12}$$

Quantity B

($$49^{7}$$)$$C_{26}$$


$$n$$ is an even integer greater than $$2$$.

Quantity A

$$\frac{n!}{(\frac{n}{2})!}$$

Quantity B

2($$\frac{n}{2}$$)!




The figure above represents a game board with a chip at staring point M. On successive plays, the chip may be moved along the lines from one labled point to an adjacent labled point, but may not be moved to the same point twice. Along how many different paths can the chip be moved from M to N in this game?
In a probability experiment, $$R$$, $$S$$, and $$T$$ are events such that $$P(S)=P(T)=x$$, $$P(R)=kx$$, and $$P(R$$ or $$S) \lt P(S$$ or $$T)$$, where $$k$$ and $$x$$ are positive numbers. Events $$R$$ and $$S$$ are mutually exclusive, and events $$S$$ and $$T$$ are independent.

Quantity A

$$k$$

Quantity B

$$1-x$$




A box contains 12 candies of four different flavors. The table above shows the numbers of candies of each flavor. If 2 candies are to be selected at random from the box, without replacement, what is the probability that of the 2 candies selected one will be a caramel candy and the other will be a cherry candy?
Although a dedicated reader of the book can ____________ a brief chronology of Chappelle`s life, the book is nevertheless not a true biography of Chappelle.
The problem a generation ago was not the new art itself but the heightened intensity of conviction surrounding it, which is thankfully absent in our wonderfully _____________ times.
The ____________ of native South American textiles at the time of the Spanish conquest should not be surprising: it represented the apogee of one of the world`s oldest and most sophisticated weaving and dyeing traditions.
The field suffers from being puffed up with its own importance, and that attitude of ______________ seems to infect very professional utterance.
Recent advances in the study of desert varnish have been a boon to geologists, allowing them to date surface features and establish regional histories in ___________ detail.
The author`s account of her ordeal could easily have been _____________, sugar-coated with inspiration and soggy with tears; instead, it finds her writing with candor about her struggles and describing them with a rare intimacy.

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