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A telephone system has $$n$$ telephone lines. For each of the $$n$$ lines, the event that the line will fail during a certain reliability test has probability 0.3, and these $$n$$ events are independent. If the probability that at least one of the n lines will not fail during the reliability test is greater than 0.99, what is the minimum value of $$n$$?
$$n \gt 10,000$$

Quantity A

The thousands digit of $$\frac{n}{8}$$

Quantity B

$$7$$






In the sequence shown, each term after the first is 1 greater than the preceding term. If the sum of all the 99 terms of the sequence is 99, then what is the value of the first term of the sequence?
a is a positive integer.

x is the remainder when 15a is divided by 6

Quantity A

x

Quantity B

2


|x| ≤ 6 and |y| ≤ 4

x and y are integers, where x≠0. M is the greatest possible value of |$$\frac{y}{x}$$|.

Quantity A

M

Quantity B

1


$$a$$ and $$b$$ are positive integers and $$a \lt b$$.

Quantity A

$$\frac{1}{\frac{1}{a}+\frac{1}{15}+\frac{1}{14}+\frac{1}{13}+\frac{1}{12}}$$

Quantity B

$$\frac{1}{\frac{1}{b}+\frac{1}{15}+\frac{1}{14}+\frac{1}{13}+\frac{1}{12}}$$


A certain factory has two work shifts. There are 840 employees on the day shift and 700 on the evening shift. The ratio of the number of male employees to the number of female employees is the same for both shifts. If the number of female employees on the day shift is 252, what is the number of male employees on the evening shift?


The table above shows a family`s monthly budget for last month and a comparison of this month`s budget with last month`s budget. Which of the following could be the amount budgeted for discretionary spending this month?

Indicate all such amounts.
The total revenue that firm P receives from the sale of a particular item is determined by multiplying the number of the items it sells by the price of the item. If the price of the item is to be decreased by 20 percent, by what percent must the number of the items sold increase to keep the total revenue unchanged?
It costs d dollars to buy t thumbtacks. At this rate, what is the cost of t+2,500 thumbtacks, in dollars?
Three printers, $$X_1$$, $$X_2$$ and $$X_3$$, work only at their respective constant rates. Working together,$$X_1$$, $$X_2$$ and $$X_3$$ can complete a certain job in 9 hours; working together, $$X_2$$ and $$X_3$$ can complete the same job in 12 hours. Working alone, how many hours will it take $$X_1$$ to complete the job?
y > 1

Quantity A

100$$y^{2}$$

Quantity B

225($$y^{2}$$ - 1)


x≠0

y≠0

x+y≠0

Quantity A

$$x^{-3}$$+$$y^{-3}$$

Quantity B

$$(x+y)^{-3}$$


The function f is defined by f(x) = $$2^{-x^{2}}$$ for all integers x. Which of the following could be the value of f(x)?

Indicate all such values.
The equation $$x^{3}$$ - $$x^{2}$$-2x=0 has three different roots.

Quantity A

The product of the three roots

Quantity B

-2


If the sum of two numbers is 9, what is the greatest possible value of the product of the two numbers?

Give your answer as a decimal.
The operation is defined by x✸y=$$\frac{x^{2}}{y}$$+$$\frac{x}{y}$$ for all numbers $$x$$ and $$y$$, where $$y \neq 0$$. What is the value of $$(9✸ (-9))+((-9) ✸9)$$?
Line l and k are perpendicular and intersects at point (-4, 4). If line k passes through the origin, then what is the x-intercept of line l?
In plane P, point Q is on line l.

Quantity A

The number of points in plane P whose distance from line l is 2 and whose distance from point Q is 3

Quantity B

4




A box manufacturer is designing a closed box in the shape of a rectangular solid. The ratio of the lengths of the sides of the box is 1 to 2 to 3. The total surface area of the box is 550 square inches. What is the volume of the box, in cubic inches?

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