Archive for November, 2007

A way to multiply

Friday, November 30th, 2007

A way to multiply with parabolas

- Do you want to hear about my latest invention?
- Do I have a choice?
- It is an easy way to multiply numbers.
- You mean, reaching for a calculator?
- Let’s say you want to multiply 2 by 3.
- I want that all the time.
- Join the points (-2, 4) and (3,9).
- Where did those points come from?
- They are (-a, a2) and (b, b2).
- OK.
- Where does the line you drew intersect the y-axis?
- Amazing! Does it always work?

Source: Wild about math.

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Friday, November 30th, 2007

Willem de Kooning

The trouble with being poor is that it takes up all of your time. – Willem de Kooning

A question of trust

Thursday, November 29th, 2007

Face of a person

Would you trust this man?

Quote

Thursday, November 29th, 2007

Dick Cavett

There’s so much comedy on television. Does that cause comedy in the streets? – Dick Cavett

Running count

Wednesday, November 28th, 2007

The Count, Sesame Street

I read somewhere that the Greek mathematicians always carried a bag of stones with them in case they had to calculate something. That may be why the etymology of ‘calculus’ is ‘stone (used in reckoning)’.

Be that as it may, counting is not easy. Especially when you are disrupted. Flight attendants sometimes use a little device they click for every passenger to get a correct head count.

The latest fad is a step counter to stimulate your exercise walks. Today’s challenge is to explain how a step counter works.

A related puzzle. When a soccer player is substituted during a game, sometimes how many km he has run is displayed on the TV screen. How on earth is that calculated?

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Wednesday, November 28th, 2007

Stephen Fry

If ignorance is bliss, why aren’t there more happy people in the world? – Stephen Fry

Heading for the beach

Tuesday, November 27th, 2007

Beach

The other day I took a ride to the beach with a friend of mine. Part of our conversation follows.

- I know that one and six is six. But, is two and five 10?, he asked.
- Not at all, I replied, two and five is twelve.
- Really? Then what is 3 and 3?, he asked.
- Seventeen, I answered.
- Ah, I think I get it now, he said.

What were we talking about?

Problem source: Car Talk.

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Tuesday, November 27th, 2007

Albert Szent-Györgyi

Discovery consists of looking at the same thing as everyone else and thinking something different. – Albert Szent-Györgyi

May I read your mind?

Monday, November 26th, 2007

Not animated

Click here for a little mind trick.

Can you explain it?

If you give up, listen to this interview with Keith Devlin.

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Monday, November 26th, 2007

Jerry Seinfeld

It’s only money. – Jerry Seinfeld