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'Mathemagician' Arthur Benjamin To Perform In La Jolla

"The Magic of Math: Solving for x and Figuring Out Why by Arthur Benjamin
"The Magic of Math: Solving for x and Figuring Out Why by Arthur Benjamin
'Mathemagician' Arthur Benjamin To Perform In La Jolla
'Mathemagician' Arthur Benjamin To Perform In La Jolla GUEST:Arthur Benjamin, author, "The Magic of Math: Solving for x and Figuring out Why."

You want to do with math anymore you don't have to. Just let your computer or your abs handle it for you. Getting into the nitty-gritty of numbers just isn't an experience anymore. That is a shame according to my next guest. Because numbers are mysterious, surprising, solid and satisfying and even magical. They can help lead you to more logical decision-making in all aspects of your life. Or perhaps even more important, they are fun. Joining me is now Arthur Benjamin , he is the author of, "The Magic of Math: Solving for x and Figuring Out Why" . He is a professor of mathematics at Harvey Mudd College. The program. It's good to be here Maureen. You call yourself a mathematician -- I am a Professor of math and I'm also a magician. I performed all over the world. What I've done for the last decade is combined these passions for math and the magic. One thing I do is I demonstrate and explain how to do math in your head faster than a calculator. Explain for us. For example, Maureen, do you have a calculator with you perhaps on your phone? I actually do not, but I'm sure many listeners do. Blisters will be able to verify this then. One of my specials -- specialties is multiplying numbers. Especially squaring numbers like a number time it self for example five squared is 25. Because five times itself is 25. Now if the listeners block calculator, hopefully not while driving, if you give me a ticket number, I will square as quickly as they can do it on a calculator. Okay, 23. Spy 29. -- How about 529. That will give you two 79,841. I am hearing that you got it. How did you do that? In broad strokes what I am doing is I am doing all of my calculations from left to right. That is the opposite of how we are taught to do it on paper. On paper we do it from right to left. If you remember algorithms you learn in school coffers to come up with the ones digit then attends, but that is backwards. We read numbers left to right. We pronounce numbers left to right. We say 529. With a little practice you can and should calculate left to right for one thing, the numbers on the left are way more important than the numbers on the right. Right? It's more important to know that your numbers a little over 200,000 Right? It's more important to know that your numbers a little over 200,010 note that the answer and then one. Because we always say and change. So when you work from left to right you get an instant feel for the magnitude of the answer. That is important. I think it's more important for people to be able to do mental arithmetic density pencil and paper arithmetic. Because any problem that requires paper, yes, as you said in the introduction, you block calculator. But there's only times in life when you don't want to doing that. When you're reading the newspaper, you don't bring a calculator next you as you read, oh my gosh this project is going to cost how many millions of dollars and look at how many people are in the community, how much does it cost everyone? You don't pull out the calculator, it's good to have a good gut feeling. Are we talking about a few tens of dollars or if you hundreds of dollars per person. That's what you want. When you are listening to a speech or when you're at a business meeting, you might not want to pull cochlear out. But it's good to have a good number cents. That is what mental math develops. Arthur Benjamin author of "The Magic of Math: Solving for x and Figuring Out Why" . You also talk about the magic of the number nine. What is that? Let's do an experiment. I want you and your listeners to think of a number between 20 and 100. It may be between 20 and 50 if you want to make it easier on yourself. But any number from 2200 is fine. I want you to add the digits of your number together now subtract that from your original number. Now you are thinking of a number that you didn't even know what you're going to be thinking about. Take the digits of that number together -- And that is nine. I hope your listeners did to their -- did TOO. that the magical property of the number nine. As a kid I thought it was a cool number. And part of what that is based on, if you think about the multiples of nine, nine, 18, 27, 36 and so on. When you add the digits of those numbers together, you always get nine. Or as the numbers get larger you get multiples of nine, they will add up to 18 or 27, etc. As a kid I thought that was absolutely magical. There was so much about math that I thought was magical. That's what I want to share with my audiences and my readers. It's not just -- we spent all this time in school learning stuff that's going to be on a test. We don't learn the stuff that just makes you say, wow, this is pretty cool. It would be as if we spent all of our music classes learning how to draw our notes properly, and never really got to listen and enjoy the music. I think that's what we doing mathematics too often. Why do you think some students tend to give up on me. Part of it is math is a very exacting subject. When you are asked to do an arithmetic problem, there really is just one right answer. And sometimes as Americans, we like some wiggle room. Where in math, you cannot really BS your way to the answer, you either know it or you don't. The unforgiving as of math is scary to people. On the other hand, what I loved about math and still do, is that even though there may only be one answer, there are usually many, many different approaches to getting to that answer. I love the fact that you could take a problem, do it lots and lots of different ways, and if you are careful, you would always get the same answer. I found that consistency of mathematics to be absolutely beautiful. Did number sequences, we heard a lot about sequences like the Fibonacci numbers. The Fibonacci numbers are my favorite collection of numbers. In fact I have an entire chapter desk chapter on the magic of the even Archie numbers. -- Magic of the even not she number Fibonacci number's. They are as easy to understand as one plus one which is to. Now I take the numbers one and two and add those to get three, and 2+3 is five. Now I have three and five are my last two numbers. I add those together to get a. And 5+8 is 13. We are playing leapfrog with our numbers. These numbers go out forever. And yet these numbers show up in nature surprisingly often. Example, the number of battle petals -- petals on a flower, there are more flowers that five or eight petals than our flowers that have four petals. The number of spirals on a sunflower or pinecone, is often a even Archie -- Fibonacci numbers and interest -- numbers. People use them in interesting ways. Their use in the stock market sometimes, they can be used in the art, this is a little bit of looking for faces in the clouds. You will find him when you're looking for them. But there are some aspects of the Fibonacci that cannot be denied. And they had patterns are so beautiful which I go into in the book. What is the real point of your math magic shows? Is it to spark interest in math? The point of the show is not for the audience to see how smart I am, but rather how smart they can be. The process of that lightbulb going off and understanding why things work is so exciting. It is so satisfying. And unfortunately, we don't -- we will have an experience with a bad teacher or two that can really derail us and make us feel like we can never understand something. That is too bad because math is such an important subject. Nothing opens more doors professionally, and I'm talking to your students are high school students or college students, when they go out into the workforce or look into graduate school, nothing opens more doors been having a solid math background. Nothing closes more doors been feeling insecure about your quantitative abilities. Don't let that bad teacher, it's bad enough that you have to have that person for a year, don't let them ruin the rest of your years. Just because they didn't explain math all that well. What is your advice to parents who would like to get the kids interested in math? Maybe they had that bad teacher. Where can they go next? The first advice I'd like to give, don't give up. When some of comes home, your son or daughter comes home and they say, I can't do this matter. Pretend -- I can't do this math. Pretend they said they can't do the reading. You would never tell a student that they couldn't pronounce a sound and you're just not a good reader. You would never say that. They know how important it is to be literate. In this day and age, in the 21st century is even more important that we are innumerate. Again, because all the possibilities that math brings to the table. If you are a parent that says, that's fine but even I don't understand the math. We are that today with the new curriculum change. A lot of people say they are doing the math differently. I can't help. My advice there as well, do not give a year -- don't give up. In either meet with the teacher or hire a tutor. It is worth it. It probably cost less than a tutor -- babysitter to find a high school student. If your daughter is complaining about math in middle school, buying a high school girl who is really good at math with good social skills who can help. Ditto if your son is having trouble. It is so worthwhile, and the attitude adjustment. When I do my competitions I want people to come out with a different attitude about math and had before. Is there a discipline about understanding numbers that has to be learned when you are young? Can adults decide that they want to go back and try to figure out some of the stuff but they never figured out when they were in school? We all get derailed at sometime. For some people, I was doing fine until geometry or calculus or maybe even much earlier. I got stuck at long division or fractions. I to think that if the crucial in matters that all kids memorize their multiplication tables and know those solidly. I think it's great to have intuitive, even tactile understanding how numbers operate, but you still need to have a fundamental level you need to know that 6×4 is 24 without having to go through any funny processes. That just has to be hardwired. And kids, of course, what else are they thinking about? They had the time and the space and the room to memorize these tools. It doesn't have to be boring or treacherous, you can make games out of it. Hopefully teachers are making games out of it so it's a fun process. But that is fundamental. What you have a solid understanding of arithmetic, which is the math that we use mostly in our daily lives, I think adults who use never longtime can come back to it. They can learn the next higher level math like algebra. Can I do a magic trick for the audience? If it's really short. I want everyone to think of a number between one and 10. Double that number, now I want you to add an -- add 10. Now divide by 2. Now subtract the number that you started with. And if my vibrations are accurate, I think you are thinking of the number five. Yes. I have to and if there. Arthur Benjamin , author of, "The Magic of Math: Solving for x and Figuring Out Why" . You will hear so much more from him at works tomorrow night at seven at 7:30 PM. Thank you so much. My pleasure.

Try Some Math Magic

Think of a number between 1 and 10.

Double that number.

Add 10 to it.

Divide the number by 2.

Subtract the number that you started with.

Are you thinking of the number 5? (You should be, or give it another try.)

Arthur Benjamin loves math.

"I've always gotten along famously with numbers," Benjamin said.


A professor of mathematics at Harvey Mudd College, Benjamin, who calls himself a "mathemagician," is on a mission to share the magic of math with others. He performs math magic shows around the world and has given three Ted talks on the subject.

"The point of my shows is not for the audience or the students to see how smart I am, but how smart they can be," Benjamin said. "I want to show them ways of working with numbers that seem magical but are quite fun and easy to do."

In his new book, "The Magic of Math: Solving for x and Figuring Out Why" Benjamin uses mental magic tricks to engage his reader in solving math equations. Benjamin said he hopes teachers and parents use his math magic to help kids who might be frustrated with math or have given up.

"I'd like to think that my way of presenting the math is fun and is sometimes motivated by magic tricks," Benjamin said. "But we also get down to business and learn the crucial steps."

Benjamin will be performing math magic at 7:30 p.m. Wednesday at Warwick's at 7812 Girard Ave. in La Jolla.