At a certain theater, the cost of each adult's ticket is $5 and the cost of each child's ticket is $2. What was the average (arithmetic mean) cost of all the adults' and children's tickets sold at the theater yesterday?

(1) Yesterday the ratio of the number of children's tickets sold at the theater to the number of adults' tickets sold at the theater was 3 to 2.
(2) Yesterday 80 adults' tickets were sold at the theater.

In 1984 a certain union had a total of 15,600 members. Was the percent increase in the total number of members in the union from 1984 to 1985 greater than that from 1985 to 1986 ?

(1) From 1984 to 1985 the total number of members in the union increased by 781, and from 1985 to 1986 the total number of members in the union again increased by 781.
(2) In 1985 the union had a total of 16,381 members, and in 1986 the union had a total of 17,162 members.

What was a certain company's revenue last year?

(1) Last year the company's gross profit was $4,100.
/>(2) Last year the company's revenue was 50 percent greater than its expenses.

If Mary always takes the same route to work, how long did it take Mary to get to work on Friday?

(1) It took Mary 20 minutes to get to work on Thursday.
(2) Mary's average speed on her trip to work was 25 percent greater on Thursday than it was on Friday.

What is the result when x is rounded to the nearest hundredth?

(1) When x is rounded to the nearest thousandth the result is 0.455.
(2) The thousandths digit of x is 5.

The numbers x and y are not integers. The value of x is closest to which integer?

(1) 4 is the integer that is closest to x + y.
(2) 1 is the integer that is closest to x - y.

If k is a line in the xy-plane, what is the slope of k ?

(1) The x-intercept of k is 2.
(2) The y-intercept of k is 3.

If d is a positive integer and f is the product of the first 30 positive integers, what is the value of d ?

(1) 10^d is a factor of f.
(2) d > 6

Warehouse W's revenue from the sale of sofas was what percent greater this year than it was last year?

(1) Warehouse W sold 10 percent more sofas this year than it did last year.
(2) Warehouse W's selling price per sofa was $30 greater this year than it was last year.

If @ denotes one of the four arithmetic operations addition, subtraction, multiplication and division, what is the value of 1 @ 2 ?

(1) n @ 0 = n for all integers n.
(2) n @ n = 0 for all integers n.