#### Quantity A

The standard deviation of 11, 22 and 33

#### Quantity B

The standard deviation of 111, 222 and 333

n > 2
List M={2, n, n, n}
List N={2, 2, 2, n}

#### Quantity A

The standard deviation of List M

#### Quantity B

The standard deviation of List N

The preceding frequency distributions represent two groups of data. Each of the data values is a multiple of 10.

#### Quantity A

The standard deviation of distribution C

#### Quantity B

The standard deviation of distribution D Set A={3, 5, 7, 8, 8, 9, 10, 11, 12}
Set B={3, 5, 7, 9, 10, 11, 12}

#### Quantity A

The standard deviation of all the numbers in Set A

#### Quantity B

The standard deviation of all the numbers in Set B

A set of numbers include 1, a, 7 (a≥0)
a must be which of the following integer so that the standard deviation of the set of is the lowest?
A set of numbers include 4, 6, 12, 14, X
X must be which of the following integer so that the standard deviation of the set of is the lowest?
Set A={500, 600, 700, 900, 1200}
Set B={500, 600, 800, 900, 1200}

#### Quantity A

The standard deviation of all the numbers in Set A

#### Quantity B

The standard deviation of all the numbers in Set B

If x is the standard deviation of a, b, c, d, e, and y is the standard deviation of a-3, b-2, c, d+2, e+3.

x

y

#### Quantity A

The standard deviation of a, b, c, d and e

#### Quantity B

The standard deviation of a+1, b, c, d and e-1

A list of numbers has a mean of 8 and a standard deviation of 2.5. If x is a number in the list that is 2 standard deviations above the mean, what is the value of x?
For a certain distribution, the measurement 12.1 is 1.5 standard deviations below the mean, and the measurement 17.5 is 3.0 deviations above the mean. What is the mean of the of distribution?
The distribution of the numbers of hours that students at a certain college studied for final exams has a mean of 12 hours and a standard deviation of 3 hours. Which of the following numbers of hours are within 2 standard deviations of the mean of the distribution?
Indicate all such numbers
A random variable Y is normally distributed with a mean of 200 and a standard deviation of 10.

#### Quantity A

The probability of the event that the value of Y is greater than 220

#### Quantity B

$\frac{1}{6}$

Set Y is normally distributed with a mean of 50 and a standard deviation of 5.4.

#### Quantity A

The percentage of number between 42.8 to 44.6

#### Quantity B

The percentage of number between 53.6 to 55.4

A survey of 5,500 book readers found that the number of books read per year was approximately normally distributed with mean 19.0 and standard deviation 2.0. Which of the following is the best description of the numbers of books read per year by the 880 book readers who read the most books? The result of a survey is normally distributed with a mean of 500 and a standard deviation of 100. If the number of variables ranging 500 to 600 is 10,200 numbers, then how many numbers in the survey are less than 400?
x and y are normally distributed with the same mean 0, and p(x < 1)=p(-1 < y < 1)

#### Quantity A

The standard deviation of x

#### Quantity B

The standard deviation of y

In a normal distribution of variable w, the mean is 60, while the standard deviation is 30.

#### Quantity A

The probability that 45 < w < 60

#### Quantity B

The probability that w > 95

The random variable Y is normally distributed with a mean of 470, and the value Y = 340 is at the 15th percentile of the distribution. Of the following, which is the best estimate of the standard deviation of the distribution?
In a kindergarten, three shorter kids sit in the first row, while four taller ones sit in the second row. In how many ways can they be arranged?

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