The December Math Puzzler questions

These are the December questions in the Young Saint Louis.com's Math Puzzler contest. After having six winning entries in November, we've come up with six new puzzlers for you.

Each month, Young Saint Louis.com publishes a series of Math Puzzlers. These are primarily for your entertainment and let you have some fun with various math concepts. But, this is not a class assignment.

Mr. Math Puzzler, Wayne Hesse of Green Park Lutheran School, has come up with some unique questions. Some have illustrations while others are all-word puzzles.

Remember what he said last month, when intelligent guessing is combined with simple arithmetic, you often have a good system for finding math answers. Math professors even have a name for this approach; it's called "Guess, Check and Revise."

The main objective of the YSL.com Math Puzzlers is to have FUN. The more fun you get out of math, the more you'll learn about this very important subject.

Submit your answers to the December contest by using the form below. In January, we'll publish the names of those who answered all these questions correctly. You'll also get an explanation of the correct answers. (For answers to the November Math Puzzlers, click here.)

We're offering an ADDED BONUS for entries. Each month, we'll put all entries that answer correctly all six Puzzlers into a hat and draw for up to three $10 gift certificates from Borders Book Stores.

A note: We've made these Math Puzzlers quite challenging, especially for younger kids. But, we don't mind if you solicit help from a parent or older brother or sister. In fact, you might want to make this a family activity.

Here's how to enter:

1. Print out the following entry form.
2. Fill out your name, address and telephone number.
3. Give your answers to the six Math Puzzlers.
4. Put your completed entry into a stamped envelope.
5. Mail your entry to:
   
   Math Puzzler Contest
   Young Saint Louis.com
   7733 Forsyth Blvd., Suite 350
   Clayton, MO 63105
   
   
6. All entries must be postmarked by the 15th of the month to be eligible for a book prize.

----------Clip here to make entry----------

Entry for December, 2001, Math Puzzler Contest:

Name: _____________________________________

Address: ___________________________________

City:_____________________, State:______ ZIP_______

Contact phone no.(____)____________________

 

The Math Puzzlers
(December 2001)

1. You have seven coins. Five of them weigh the same and two are slightly heavier. (The heavier coins are equal in weight to each other.) Using only the balance scale, which is the fewest number of weighings needed to determine which coins are the heavier ones?

 

Answer:___________

 

2. Place the digits 1 through 7 in the boxes below so that each three-box-line, including the diagonals, add up to 12.

 

Answer:___________

 

3. What is the smallest number that can be divided by 6, leaving a remainder of 5; divided by 5 and leaving 4, and divided by 4 and leaving 3?

 

Answer:___________

 

4. Ron and Jane compete in a car rally, going several times around a closed circuit. Ron can drive the circuit in 25 minutes, but Jane takes 30 minutes. If the two drivers start at the same time, how long will it take Ron to lap Jane?

 

Answer:___________

 

5. Pymm has many dragons. A few years ago, one of these dragons, Alaranthus, though not fully grown, weighed one thousand pounds plus two-thirds of his own weight. How much did Alaranthus weigh?

 

Answer: ___________

 

6. Betty has 13 chains with three links in each chain. She would like to connect all 13 chains together to form one continuous circular chain. If a jeweler charges $4 to cut a link open and $10 to weld it back together again, what is the cheapest cost by which Betty can have this done?

 

Answer:__________