A photographer will arrange 6 people of 6 different heights for photograph by placing them in two rows of three so that each person in the first row is standing in front of someone in the second row.  The heights of the people within each row must increase from left to right, and each person in the second row must be taller than the person standing in front of him or her.  How many such arrangements of the 6 people are possible?

In the sequence 1, 2, 4, 8, 16, 32, …, each term after the first is twice the previous term.  What is the sum of the 16th, 17th, and 18th terms in the sequence?

When Leo imported a certain item, he made a 7 percent import tax on the portion of the total value of the item in excess of  $1,000.  If the amount of the import tax that Leo paid was $87.50, what was the total value of the item?

Ifx > 0, then ~$\frac{1}{\sqrt{2x}+\sqrt{x}}=$~

The figure shows a square patio surrounded by a walkway of width x meters.  If the area of the walkway is 132 square meters and the width of the patio is 5 meters greater than the width of the walkway, what is the area of the patio, in square meters?

In Town X, 64 percent of the population are employed, and 48 percent of the population are employed males.  What percent of the employed people in Town X are females?

Ann, Carol, and Judy paid a total of $45 for their dinner at a restaurant.  If Ann paid ~$\frac{2}{5}$~ of the total amount, Carol paid $17, and Judy paid the rest, what fraction of the total amount did Judy pay?

If 10⁵⁰ – 74 is written as an integer in base 10 notation, what is the sum of the digits in that integer?

In a corporation, 50 percent of the male employees and 40 percent of the female employees are at least 35 years old.  If 42 percent of all the employees are at least 35 years old, what fraction of the employees in the corporation are females?

A set of numbers has the property that for any number t in the set, t + 2 is in the set.  If –1 is in the set, which of the following must also be in the set?

I. -3
II. 1
III. 5