Time and Distance

A puzzle from Martin Gardner’s column in Math Horizons, November 1995:

Driving along the highway, Mr. Smith notices that signs for Flatz beer appear to be spaced at regular intervals along the roadway. He counts the number of signs he passes in one minute and finds that this number multiplied by 10 gives the car’s speed in miles per hour. Assuming that the signs are equally spaced, that the car’s speed is constant, and that the timed minute began and ended with the car midway between two signs, what is the distance from one sign to the next?

Click for Answer

Note

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The same goes for the old Facebook page, which hasn’t been updated since 2012. The new page is here. Thanks.

Team Spirit

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Thomas Huxley’s Evolution and Ethics took China by storm — phrases such as the strong are victorious and the weak perish resonated in the national consciousness and “spread like a prairie fire, setting ablaze the hearts and blood of many young people,” noted philosopher Hu Shih.

People even adopted Darwin’s ideas as names. “The once famous General Chen Chiung-ming called himself ‘Ching-tsun’ or ‘Struggling for Existence.’ Two of my schoolmates bore the names ‘Natural Selection Yang’ and ‘Struggle for Existence Sun.’

“Even my own name bears witness to the great vogue of evolutionism in China. I remember distinctly the morning when I asked my second brother to suggest a literary name for me. After only a moment’s reflection, he said, ‘How about the word shih [fitness] in the phrase “Survival of the Fittest”?’ I agreed and, first using it as a nom de plume, finally adopted it in 1910 as my name.”

(Hu Shih, Living Philosophies, 1931.)

Green Activism

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There must be a story behind this one: In 1900 Ludwig Ederer patented an “alarm bed” to wake an attendant when a greenhouse grows too cold.

If the steam pressure in the boiler drops, the bed suddenly tilts upright, “so that the sleeper will slide or roll off, thus reminding him that the steam within the pipe system is below a certain point, endangering the life of the plants within the greenhouse.”

After he’s stoked the fire the attendant can go back to bed and dream about getting a better job.

Lineup

A group of children are standing outside a room. Each wears a hat that’s either red or blue, and each child can see the other children’s hats but not her own. At a signal they enter the room one by one and arrange themselves in a line partitioned by hat color. How do they manage this without communicating?

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Dry Humor

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Jokes from the Dust Bowl:

The drought was so bad that when one man was hit on the head with a rain drop, he was so overcome that two buckets of sand had to be thrown in his face to revive him. Housewives supposedly scoured pans clean by holding them up to a keyhole for sandblasting, and sportsmen allegedly shot ground squirrels overhead as the animals tunneled upward through the dust for air. Some farmers claimed that they planted their crops by throwing seed into the air as their fields blew past and that birds flew backwards to keep the sand out of their eyes.

In 1935 Dalhart Texan editor John McCarty founded a Last Man’s Club in which each member took an oath: “In the absence of an act of God, serious family injury, or some other emergency, I pledge to stay here as the last man and to do everything I can to help other last men remain in this country. We promise to stay here till hell freezes over and skate out on the ice.”

As a joke he proposed to build a huge hotel amid the dunes north of Dalhart where tourists would pay “fancy prices” for the privilege of witnessing the “noble grandeur an imposing beauty of a Panhandle sandstorm.” “We’ve got the greatest country in the world if we can just get a few kinks straightened out,” he wrote. “Let’s keep boosting our country.” About 100 people joined the club; more said they wanted to do so but acknowledged they were afraid they’d have to leave.

(From R. Douglas Hurt’s The Dust Bowl: An Agricultural and Social History, 1981.)

In a Word

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interturb
v. to disturb by interrupting

In late 1908 Douglas Mawson, Alastair Mackay, and Edgeworth David left Ernest Shackleton’s party in hopes of discovering the location of the South Magnetic Pole. On Dec. 11, while Mackay left the camp to reconnoiter, David prepared to sketch the mountains and Mawson retired into the tent to work on his camera equipment:

I was busy changing photographic plates in the only place where it could be done — inside the sleeping bag. … Soon after I had done up the bag, having got safely inside, I heard a voice from outside — a gentle voice — calling:

‘Mawson, Mawson.’

‘Hullo!’ said I.

‘Oh, you’re in the bag changing plates, are you?’

‘Yes, Professor.’

There was a silence for some time. Then I heard the Professor calling in a louder tone:

‘Mawson!’

I answered again. Well the Professor heard by the sound I was still in the bag, so he said:

‘Oh, still changing plates, are you?’

‘Yes.’

More silence for some time. After a minute, in a rather loud and anxious tone:

‘Mawson!’

I thought there was something up, but could not tell what he was after. I was getting rather tired of it and called out:

‘Hullo. What is it? What can I do?’

‘Well, Mawson, I am in a rather dangerous position. I am really hanging on by my fingers to the edge of a crevasse, and I don’t think I can hold on much longer. I shall have to trouble you to come out and assist me.’

I came out rather quicker than I can say. There was the Professor, just his head showing and hanging on to the edge of a dangerous crevasse.

David later explained, “I had scarcely gone more than six yards from the tent, when the lid of a crevasse suddenly collapsed under me. I only saved myself from going right down by throwing my arms out and staying myself on the snow lid on either side.”

Mawson helped him out, and David began his sketching. The party reached the pole in January.

Young Riders

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Sons of Jack “Catch-‘Em-Alive” Abernathy, the youngest U.S. Marshal in history, Louis and Temple Abernathy inherited their father’s self-reliance: In 1910, when they were 10 and 6 years old, they rode on horseback from their Oklahoma ranch to Manhattan to greet Theodore Roosevelt as he returned from Africa. After riding behind Roosevelt’s car in a ticker-tape parade, they drove home in a new car.

The following year, apparently bored, they accepted a $10,000 challenge to ride on horseback from New York to San Francisco in 60 days or less, never eating or sleeping indoors. They missed the deadline by two days but still established a speed record. And in 1913 they rode by motorcycle from Oklahoma to New York City.

The two went on to successful careers in law and oil. “Teach a boy self-reliance from the moment he tumbles out of the cradle, make him keep his traces taut and work well forward in his collar, and 99 times out of a hundred his independence will assert itself before he is 2 years old,” their father told a newspaper after their first trip. “That’s my rule, and if you don’t think I’ve taken the right tack talk to my boys for five minutes and they’ll convince you that they are men in principles even if they are babies in years. God bless ’em.”