The Impossible Question : Part 1

How Would You Move Mount Fuji?: Microsoft's Cult of the Puzzle - How the World's Smartest Companies Select the Most Creative Thinkers
by William Poundstone

Why are beer cans tapered on the ends? How many piano tuners are there in the world? Why does a mirror reverse right and left instead of up and down?

For years, Microsoft and other high-tech companies have been posing riddles and logic puzzles like these in their notoriously grueling job interviews. Now "puzzle interviews" have become a hot new trend in hiring. From Wall Street to Silicon Valley, employers are using tough and tricky questions to gauge job candidates' intelligence, imagination, and problem-solving ability-qualities needed to survive in today's hypercompetitive global marketplace.

For the first time, William Poundstone reveals the toughest questions used at Microsoft and other Fortune 500 companies - and supplies the answers. He traces the rise and controversial fall of employer-mandated IQ tests, the peculiar obsessions of Bill Gates (who plays jigsaw puzzles as a competitive sport), the sadistic mind games of Wall Street (which reportedly led one job seeker to smash a forty-third-story window), and the bizarre excesses of today's hiring managers (who may start off your interview with a box of Legos or a game of virtual Russian roulette).

How Would You Move Mount Fuji? is an indispensable book for anyone in business. Managers seeking the most talented employees will learn to incorporate puzzle interviews in their search for the top candidates. Job seekers competing in today's tight market will discover how to tackle even the most brain-busting questions, and gain the advantage that could win the job of a lifetime.

And anyone who has ever dreamed of going up against the best minds in business may discover that these puzzles are simply a lot of fun. Why are beer cans tapered on the end, anyway?

Chapter 1

In August 1957 William Shockley was recruiting staff for his Palo Alto, California, start-up, Shockley Semiconductor Laboratory. Shockley had been part of the Bell Labs team that invented the transistor. He had quit his job and come west to start his own company, telling people his goal was to make a million dollars. Everyone thought he was crazy. Shockley knew he wasn't. Unlike a lot of the people at Bell Labs, he knew the transistor was going to be big.

Shockley had an idea about how to make transistors cheaply. He was going to fabricate them out of silicon. He had come to this valley, south of San Francisco, to start production. He felt like he was on the cusp of history, in the right place at the right time. All that he needed was the right people. Shockley was leaving nothing to chance.

Today's interview was Jim Gibbons. He was a young guy, early twenties. He already had a Stanford Ph.D. He had studied at Cambridge too - on a Fulbright scholarship he'd won. Gibbons was sitting in front of him right now, in Shockley's Quonset hut office. Shockley picked up his stopwatch.

There's a tennis tournament with one hundred twenty-seven players, Shockley began, in measured tones. You've got one hundred twenty-six people paired off in sixty-three matches, plus one unpaired player as a bye. In the next round, there are sixty-four players and thirty-two matches. How many matches, total, does it take to determine a winner?

Shockley started the stopwatch. The hand had not gone far when Gibbons replied: One hundred twenty-six.

How did you do that? Shockley wanted to know. Have you heard this before?

Gibbons explained simply that it takes one match to eliminate one player. One hundred twenty-six players have to be eliminated to leave one winner. Therefore, there have to be 126 matches.

Shockley almost threw a tantrum. That was how he would have solved the problem, he told Gibbons. Gibbons had the distinct impression that Shockley did not care for other people using "his" method.

Shockley posed the next puzzle and clicked the stop-watch again. This one was harder for Gibbons. He thought a long time without answering. He noticed that, with each passing second, the room's atmosphere grew less tense. Shockley, seething at the previous answer, now relaxed like a man sinking into a hot bath. Finally, Shockley clicked off the stopwatch and said that Gibbons had already taken twice the lab average time to answer the question. He reported this with charitable satisfaction. Gibbons was hired.

Find the Heavy Billiard Ball...

Fast-forward forty years in time - only a few miles in space from long-since-defunct Shockley Semiconductor - to a much-changed Silicon Valley. Transistors etched onto silicon chips were as big as Shockley imagined. Software was even bigger. Stanford was having a career fair, and one of the most popular companies in attendance was the Microsoft Corporation. With the 1990s dot-com boom and bull market in full swing, Microsoft was famous as a place where employees of no particular distinction could make $1 million before their thirtieth birthday. Grad student Gene McKenna signed up for an interview with Microsoft's recruiter.

Suppose you had eight billiard balls, the recruiter began. One of them is slightly heavier, but the only way to tell is by putting it on a scale against the others. What's the fewest number of times you'd have to use the scale to find the heavier ball?

McKenna began reasoning aloud. Everything he said was sensible, but somehow nothing seemed to impress the recruiter. With hinting and prodding, McKenna came up with a billiard-ball-weighing scheme that was marginally acceptable to the Microsoft guy. The answer was two.

"Now, imagine Microsoft wanted to get into the appliance business," the recruiter then said. "Suppose we wanted to run a microwave oven from the computer. What software would you write to do this?"

"Why would you want to do that?" asked McKenna. "I don't want to go to my refrigerator, get out some food, put it in the microwave, and then run to my computer to start it!" "Well, the microwave could still have buttons on it too."

"So why do I want to run it from my computer?" "Well maybe you could make it programmable? For example, you could call your computer from work and have it start cooking your turkey." "But wouldn't my turkey," asked McKenna, "or any other food, go bad sitting in the microwave while I'm at work? I could put a frozen turkey in, but then it would drip water everywhere."

"What other options could the microwave have?" the recruiter asked. Pause. "For example, you could use the computer to download and exchange recipes." "You can do that now. Why does Microsoft want to bother with connecting the computer to the microwave?" "Well let's not worry about that. Just assume that Microsoft has decided this. It's your job to think up uses for it." McKenna thought in silence.

Copyright © 2003 by William Poundstone

About the Author

William Poundstone is the author of nine books, including Carl Sagan: A Life in the Cosmos, Prisoner's Dilemma, Labyrinths of Reason, and the popular Big Secrets series, which inspired two television network specials. He has written for Esquire, Harper's, The Economist, and the New York Times Book Review, and his science writing has been nominated twice for the Pulitzer Prize. He lives in Los Angeles.