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

Data sets K and T have the same number of values.Each value in K is either 0 or 2, and both 0 and 2 occur in K at least once. Each value in T is either 0 or 1,and both 0 and 1 occur in T at least once.

Quantity A

The standard deviation of the values in K

Quantity B

The standard deviation of the values in T


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

The mean and standard deviation of the 17 values in a list are 0 and 40, respectively. If one more value is included in the list, the mean of the 18 values will be 0. The standard deviation of the 18 values will be closest to which of the following?
If the product of integers a, b, c, and d is an even integer, which of the following statements about a, b, c, and d must be true?
n is a positive integer

$$x=n^{2}+7n+10

Quantity A

The remainder when x is divided by 2

Quantity B

1


Quantity A

The digit in the hundredths place in the the number 0.083

Quantity B

The digit in the hundreds place in number 1600




In the figure above, what is the perimeter of the shaded region?


Quantity A

y

Quantity B

1


One piece of candy is to be selected at random from each of 4 different boxes of assorted candies. For each of the boxes, the probability that the candy selected will be a chocolate candy is 1/10, and the 4 selections are to be made independently of each other.

Quantity A

The probability that none of the 4 pieces of candy selected will be a chocolate candy

Quantity B

$$\frac{4}{5}$$


To wake up in the morning, Doug sets two alarm clocks that operate independently of each other, in case one alarm clock fails to ring. If the probability that the first clock will ring is 0.95 and the probability that the second clock will ring is 0.90, what is the probability that neither alarm clock will ring?

Give your answer as a decimal.
The units digit of 2!+4!+6!+8!+10! Is
In a local election there are 2 candidates for mayor, 4 candidates for sheriff, and 5 candidates for dogcatcher on the ballot. In each of the three categories a voter may vote for exactly one candidate or none. How many different ways can a vote fill out the ballot?
A combination lock is set to open when the correct direction sequence is selected, either left-right-left or right-left-right, and when the correct three numbers from 1 to 60, inclusive, are selected in the correct order. If each number can be used only once, which of the following gives the number of different combinations that can be set to open the lock?
The variance of n numerical data $$ x_{1}, x_{2}, x_{3}, ..., x_{n}$$, With mean $$\bar{x}$$ is equal to $$\sqrt{\frac{S}{n}}$$, where S is the sum of the squared differences $$(x_{i}-\bar{x})^{2}$$, for 1 ≤ i ≤ n.

Data set R consists of n values and data set T consists of 2n values, where n is a positive integer. The means of the values in R and T are the same, and the variances of the values in R and T are 16 and 100, respectively. What is the variance of the values in the data set that consists of the values in R and the values in T?
The standard deviation of the five values 2, 4, 6, 8, 10 is σ. For which of the following lists is the standard deviation of the values in the list equals to σ?

Indicate all such lists.
List L consists of an odd number of consecutive integers. The median of the integers in L is 3. Which of the following statements must be true?

Indicate all such statements.


Quadrilateral ABCD is inscribed in the circle shown. What is the value of x+y?

(Note: The measure of an angle inscribed in a circle is equal to half of the measure of the central angle that subtends the same arc.)

Quantity A

The ones digit of $$208^{208}$$

Quantity B

7


If the length of each side of a regular hexagon is 6, what is the area of the regular hexagon?
Working alone at their respective constant rates, an outlet pump can empty a certain tank of water in 7 hours when the tank is initially full, and an inlet pump can fill the tank in 10 hours when the tank is initially empty. Beginning with a full tank, both pumps work simultaneously at their respective constant rates for 1 hour before the inlet pump is shut off. How many more hours would it take the outlet pump working alone to empty the tank?


In the figure, the line l and the x-axis are tangent to the circle at points P and S, respectively, and the line segment QS passed through center R of the circle. What is the slope of l?

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