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$$a_1, a_2, a_3,-..a_n,--.$$

In the sequence shown, $$a_1$$=6

and for each integer n greater than 1, $$a_n$$ is defined by

If n is even, then $$a_n$$=2+$$a_{n-1}$$ (n≥2)

If n is odd, then $$a_n$$=-8+$$a_{n-1}$$ (n≥2)

What is the value of $$a_7$$?
x-y > 0

Quantity A

|x|-|y|

Quantity B

0


The operation ⭕️ is defined by x ⭕️ y=$$\frac{1}{x}$$+$$\frac{1}{y}$$ for all positive numbers x and y. Which of the following statements must be true for all positive numbers m and r?

Indicate all such statements.
In the xy-plane, the point (3p, 5p-1) lies on the line with equation y=-$$\frac{1}{2}$$x-$$\frac{5}{3}$$. What is the value of p?

Give your answer as a fraction.
For the programming languages shown, the ratio of the greatest number of job postings in 2018 to the least number of job postings in 2018 was closest to which of the following?
For 2017, let M be the median number of job postings for the programming languages shown and let P be the median number of job postings for the programming languages shown except for PHP. What is the value of P-M?
If the numbers of job postings for each language and year except Java in 2018 were as shown, and if the range of the numbers of job postings for 2018 had been equal to that for 2017 instead of what it actually was, what would have been the number of job postings for Java in 2018?

_____thousand


The average (arithmetic mean) value of x in the frequency distribution above is 0. If a value of x is to be selected at random from the distribution, which of the following events is most likely?
x ≤ 5

y ≤ 40

Quantity A

xy

Quantity B

300


In 1970 approximately what percent of United States residents were older than 5 but younger than 65 years old?
Of the 10 selected years, which had the greatest total number of United States residents in the combined age groups of "5 years and younger" and "65 years and older"?
Of the following which best describes how the number of United States residents that were in the age-group"5 years and younger"changed from 1900 to 1940?
The number 20.0 is 2 standard deviations above the average (arithmetic mean) of the numbers in a certain list, and the number 6.5 is 3 standard deviations below the average of the numbers in the list.

Quantity A

The average of the numbers in the list

Quantity B

14.6




Pat has five matched pairs of socks and no two of the pairs are the same color. If Pat selects two socks simultaneously and at random, what is the probability that the two socks selected will be a matched pair?


The table shows values of the function $$f$$ for selected values of $$x$$. The graph of $$y=f(x)$$ is a line in the $$xy$$-plane. What is the value of $$f(1)$$?

Give your answer as a fraction.
In 1990 in neighborhood V, $$\frac{1}{3}$$ of the foreign-born population whose region of origin was Asia came from China. Approximately what fraction of the entire foreign-born population in neighborhood V came from China?
A list of the names of the people of the entire 1990 foreign-born population in neighborhood V was generated, with each person's name appearing once.The names of 2 different people will be randomly selected from the list. Which of the following is closest to the probability that both names selected will be names of people whose region of origin was "Other"?

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