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If twice the sum of the positive integers x, y, and z is divided by 7, the remainder is 1. What is the remainder if the sum of x, y, and z is divided by 7?
$$\frac{51!-50!}{50!-49!}$$=


The figure shows a large equilateral triangle partitioned into 4 regular hexagons, 3 trapezoids, and 3 smaller equilateral triangles. If all sides of the hexagons are congruent, what is the ratio of the sum of the areas of the 4 hexagons to the sum of the areas of the 3 trapezoids to the sum of the areas of the 3 smaller triangles?
Two water faucets are used to fill a certain tank. Running individually at their respective constant rates, these faucets fill the empty tank in 12 minutes and 20 minutes, respectively. If no water leaves the tank, how many minutes will it take for both faucets running simultaneously at their respective rates to fill the empty tank?


This morning Tom visited 6 Internet sites, and Andrew visited 8 Internet sites. The table shows the time, in minutes, spent visiting each site.

Quantity A

The standard deviation of the 6 times shown for Tom

Quantity B

The standard deviation of the 8 times shown for Andrew


Working simultaneously at their respective constant rates, pump $$P$$ and pump $$S$$ together pumped out $$\frac{2}{3}$$ of the water in a full tank in 1 hour 20 minutes. Pump $$P$$ then stopped working, and pump $$S$$, working alone at its constant rate, pumped out the rest of the water in the tank in 50 minutes. How many hours would it have taken pump $$P$$, working alone at its constant rate, to pump out all the water in the full tank?
A furniture store purchased sofas for a wholesale price of $400 each and sold most of them for a retail price of $560 each. In a summer sale, the retail price of the last few sofas was reduced by $$x$$ dollars, and they were sold at this reduced price. The store's profit from selling the last sofa was more than 15 percent of its wholesale price. Which of the following could be the value of $$ x$$ ?

Indicate all such values.


A social scientist conducted two experiments, experiment I and experiment II, in which the values 0, 1, 2, 3. and 4 were observed with the frequencies shown in the table above. Which of the following statistics are the same for the distribution of values observed in experiment I as they are for the distribution of values observed in experiment II?

Indicate all such statistics.
If $$n$$ is an integer greater than $$2$$, which of the following could be a prime number?
In 1990 the population of New York was approximately how many times the combined populations of Dallas and Houston?
For each city, $$D$$ represents the average daily temperature shown for July minus the average daily temperature shown for January. For how many of the cities is $$20° F< D< 35°F$$?
The normal annual precipitation shown for each city is calculated by taking the average (arithmetic mean) of the annual precipitation amounts for that city for the 30-year period 1961-1990. How many inches of precipitation would Dallas have had to receive in 1991 to raise its average annual precipitation for the 31-year period 1961-1991 to $$34.1$$ inches?
If Transit Company T will run $$60$$ trains per day, then the projected annual revenue is approximately what percent greater than the projected annual cost?
If Transit Company T will run $$40$$ trains per day for a year. approximately what is the projected average revenue per day?
Transit Company T's projected annual cost consists of staffing costs, fuel costs, and equipment costs in the ratio of 1 to 2 to 5. If the company will run $$50$$ trains per day, approximately what is the projected annual cost for fuel?
The average number of available rooms per day in 1997 was approximately what fraction of the average number of available rooms per day in 2000?
The "occupancy rate" for each year is the ratio of the average number of occupied rooms per day to the average number of available rooms per day. For which of the years shown was the occupancy rate least?
Which of the following is closest to the percent increase in the average daily room rate from 1996 to 2000?

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