1. Alyssa, Bryce, and Chris are getting ready to paint a room. Alyssa can paint the room by herself in 2 hours, Bryce can paint the room in 3 hours, and Chris can paint it in 4 hours. How long will it take Alyssa, Bryce, and Chris to paint the room if they work together?

2. Which has a larger area, a circle of radius 2 or a circle of circumference 12?

3. The mean of a set of 5 numbers is 12. One of the numbers in the set is 16. If 16 is removed from the list, what is the new mean?

9. Assuming that you can pronounce one number per second, how long would it take you to count to 1 billion, saying the numbers one after another out loud? First, make a thoughtful guess, then calculate.

8. A blueprint of a building gives a scale of 1 in. = 8 ft. If the blueprint shows the building sitting on a rectangle with dimensions 26 in. x 35 in., what is the actual area of the rectangle on which the building sits?

7. A bag contains 5 blue marbles, 4 white marbles, and 3 red marbles. If 3 red marbles are randomly selected from the bag, what is the probability that exactly 2 of the 3 marbles selected will be the same color?

4. Each year, a car is worth 8% less that it was the year before. After 3 years, the car is worth $19,311.46. What was the original value of the car?

5. What is the sum of - 1 + 2 - 3 + 4 - 5 + . . . - 99? Note that the addition and subtraction signs alternate.

6. Let a be a two-digit number and b the number obtained by interchanging the digits of a. Explain why a² - b² is divisible by 9, by 11, and also by the sum of the digits of the number a.

10. Steve and Greg have a snow-shoveling service. Their first job is to shovel a long driveway that usually takes Steve 60 minutes by himself or Greg 40 minutes by himself. This time, they are going to work together. Steve will start at one end of the driveway, and Greg will start at the other end. How many minutes will it take them to complete the job?