If x and y are integers, what is the value of x + y ?

(1) 690 < x < y < 696
(2) 692 < x < y < 695

What is the average (arithmetic mean) of eleven consecutive integers?

(1) The average of the first nine integers is 7.
(2) The average of the last nine integers is 9.

A bookstore that sells used books sells each of its paperback books for a certain price and each of its hardcover books for a certain price. If Joe, Maria, and Paul bought books in this store, how much did Maria pay for 1 paperback book and 1 hardcover book?

(1) Joe bought 2 paperback books and 3 hardcover books for $12.50.
(2) Paul bought 4 paperback books and 6 hardcover books for $25.00.

Is the integer x divisible by 6 ?

(1) x + 3 is divisible by 3.
(2) x + 3 is an odd number.

Is x + y negative?

(1) x is negative.
(2) y is positive.

In the finite sequence of positive integers K₁, K₂, K₃, . . . , K₉, each term after the second is the sum of the two terms immediately preceding it. If K₅ = 18, what is the value of K₉ ?

(1) K₄ = 11
(2) K₆ = 29

If x is a positive number less than 10, is z greater than the average (arithmetic mean) of x and 10 ?

(1) On the number line, z is closer to 10 than it is to x.
(2) z = 5x

Are at least 10 percent of the people in Country X who are 65 years old or older employed?

(1) In Country X, 11.3 percent of the population is 65 years old or older.
(2) In Country X, of the population 65 years old or older, 20 percent of the men and 10 percent of the women are employed.

The cost of delivery for an order of desk chairs was $10.00 for the first chair, and $1.00 for each additional chair in the order. If an office manager placed an order for n desk chairs, is n > 24 ?

(1) The delivery cost for the order totaled more than $30.00.
(2) The average (arithmetic mean) delivery cost per chair of the n chairs was $1.36.

What was the percent increase in the population of City K from 1980 to 1990 ?

(1) In 1970 the population of City K was 160,000
(2) In 1980 the population of City K was 20 percent greater than it was in 1970, and in 1990 the population of City K was 30 percent greater than it was in 1970.