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Quantity A

The standard deviation of the heights of 12 children whose mean height is 50 inches

Quantity B

The standard deviation of the heights of 10 children whose mean height is 60 inches




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

The lengths of phone calls made on a certain weekend by students at High School H are approximately normally distributed with a mean of 30 minutes and a standard deviation of 10 minutes. Which of the following statements must be true?

Indicate all such statements.
Let x be a positive number. The random variable R is normally distributed with mean x and standard deviation 0.25x. The random variable T is normally distributed with mean 0.5x and standard deviation 0.5x.

Quantity A

P (R <1.375x)

Quantity B

P (T <1.25x)


In a survey of educators. 40 percent reported that they used the Internet for research. Also in the survey, 65 percent reported that they used the Internet for E-mail.

Quantity A

The percent of the educators surveyed who reported that they used the Internet for both research and E-mail

Quantity B

26%




According to the table, the percent of households in 1980 with neither a microwave oven nor a central air conditioner must be in which of the following inclusive intervals?

Quantity A

The number of ordered triples ($$x_1$$, $$x_2$$, $$x_3$$), where $$x_1$$, $$x_2$$ and $$x_3$$ are non-negative integers such that $$x_1$$+$$x_2$$+$$x_3=9$$

Quantity B

$$55$$


Three numbers are to be selected at random and without replacement from the five numbers 4, 5, 7, 8 and 11. What is the probability that the three numbers selected could be the lengths of the sides of a triangle?
A bag contains 6 balls of which 2 are red and 4 are green. If 2 balls are to be chosen at random one after the other, without replacement. what is the probability that the second ball chosen will be red?
Recent research runs counter to the long-cherished notion that a small drop in body temperature during and after surgery is either ________ or actually protects the patient by slowing metabolism and reducing the body's demand for blood and oxygen.
The adipose tissue in which our bodies store fat from the food we eat has traditionally been thought of as __________, but in reality this tissue constitutes a dynamic organ, not a mere repository.
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.
If it is wrong to justify human selfishness on the basis of the alleged selfishness of nature, then it is equally mistaken to espouse ____________ merely because some animals happily assist each other.
The campaign official argued that the large swings in the candidate's approval ratings were a result not of the ____________ of the electorate but rather of the polls' margins of error and divergent methodologies.
Monarch butterflies sequester toxins in their skin to discourage predators, but black-backed orioles (Icterus abeillei) ___________ the defense: they consume only the soft insides of the butterfly.
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.
Anna Barbauld's 1804 edition of Richardson's correspondence has been (i)____________. Although she (ii)____________ many of the letters that are included and made stylistic changes throughout, often for the worse, she was, by the standards of her time, quite (iii)____________ editor with regard to her respect for the original texts.
(i) _____________ the cumbersome phraseology of contemporary critical theory, her treatise is, stylistically at least, in sharp contrast with the (ii) _____________ of the prose she is analyzing—prose reflective of a culture that values extreme linguistic compression.
Even though Our Lady of the Forest achieves clinical evenhandedness in depicting the most depressing members of a small logging town, the novel lacks a single likable character and too often runs aground on _____________ writing.
Although streams of solar particles cause beautiful auroras-the northern and southern lights—sometimes their consequences are less _____________: their electromagnetic effects, for instance, can overload power grids and damage orbiting satellites.
Science is a seemingly inexhaustible source of _____________, yet paradoxically scientists have been portrayed in recent decades as rather conservative—resisting innovation in their discipline sometimes to the point of dogmatism.

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