Math magic on display at college

Jim Smith talks to Charlie Naffziger about math.

Three dozen Lunch and Learn students were treated to Charlie Naffziger's math magic during last Thursday's class at Sisters COCC Center.

Naffziger, professor of math at Central Oregon Community College, held the group spellbound with his math wizardry and "mind reading" abilities. Many adults have a math phobia, but Charlie's brand of humor puts this to rest pretty quickly.

Passing out calculators to students to start class seemed ominous at first.

"This is math for fun and there's no grade," said Naffziger. He proceeded to lead the group through an opening number game on the calculator, which ended with everybody getting their age correctly displayed on final calculation.

"Generally, at a party, somebody will ask what I do and I have to reveal that I'm a math teacher," said Naffziger. "This usually draws the comment, 'I hate math.' That's why I want to give you the chance to do math in today's class."

Soon a noisy group was exploring hidden math gems with great enthusiasm.

He bet the class of 36 people that two of the people had the same birthday. Sure enough two people in the class were born on May 22.

Now how did he know that? Naffziger said that the odds are 50 percent of same birthday when you have 23 people, and 99 percent when you have 60 people. So he played the odds with a class of 36 and won.

Next, the group played 'Magic Square' with five columns and rows of numbers. Picking five different numbers always led to a total of '55' for each class member -- which was astonishing to most of the students.

Next was an example from 18th century philosopher and mathematician Leonard Euler's childhood. The youngster was asked "what is the sum of adding each number between 1 and 100." Euler quickly answered 5,050 (Take the first and last number added together and multiply by 50; i.e., 1+100; 2+99; 3+98, etc.).

Naffziger demonstrated exponential growth with a golf example. Noting that Central Oregon has several golf courses he asked how much would be bet starting with 5 cents on the first hole and doubling each bet, while losing, up through 18 holes. The total came to $13,107.20 by the end of the match.

Call 549-7331 for information on future programs.

Math Magic example:

1. Choose a number between two and nine.

2. Double it.

3. Add 10.

4. Multiply by 50.

5. If you have had your birthday this year, add 1,502; if not, add 1,501.

6. Subtract the year you were born in.

7. You should have a three-digit number. The first digit is your original number and the second two-digits are your age.