The Puzzler #15
Think you're smart? Try these brainteasers that recruiters use in actual job interviews.
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THIS MONTH'S CONTEST
HEADS AND TAILS
You are blindfolded. On the table in front of you are a number of ordinary coins. You are told that exactly 26 coins show heads.
Your challenge (while blindfolded): Divide the coins into two sets so that the same number of coins in each set show heads. (There is no way for you to tell, by sight or touch, which coins are showing heads or tails.)
Please email your solution to John Kador jkador@jkador.com using the subject line “Heads and Tails.” Deadline is September 1, 2009. Two responses will be selected to receive a signed copy of John Kador's How to Ace the Brainteaser Job Interview. Good luck.
BRAINTEASER: VISITING THE PYRAMIDS
A childless young man took a trip to visit the Great Pyramids of Egypt in the year 1865. He was deeply moved by the trip and vowed that one day when he was a father he would return with his son so the son could see the wonders of the Great Pyramids. The father fulfilled his vow, and in the year 1845, he and his son visited the Great Pyramids. Puzzle: How is this possible?
SOLUTION TO PREVIOUS PUZZLER: CANDLE TIME
To recap: You have two candles. Each candle takes 60 minutes to burn completely. The candles are not uniform and cannot be assumed to burn evenly. Using these two candles and nothing else, how would you time exactly 45 minutes?
We received over 50 responses. A number of you figured out that the trick is to light both ends of one candle. Here's how Timothy Brown, Financial Consultant at Bodell Overcash Anderson & Co., Inc in Jamestown, NY explained it:
Light one of the 2 candles. When this candle has burned halfway through, thus burned for 30 minutes, light the second candle. Halfway through the second candle's burn time will be 30 minutes leaving half the candle remaining. Once the second candle has burned through the remaining “half”, this will indicate 45 minutes.
The other winner, also selected at random, is Chadwick D. Richards, Financial Advisor, Waddell & Reed, Inc. Nashville, TN. Congratulations to the two winners.
John Kador is the author of 10 books. His latest book is Effective Apology: Mending Fences, Building Bridges, and Restoring Trust (Berrett-Koehler). www.effectiveapology.com
SOLUTION TO VISITING PYRAMIDS: The young man first visited the Great Pyramids in 1865 B.C. (Before the birth of Christ). 20 years later, in 1845 B.C., the father fulfilled his vow.
