In a class I taught to seniors who seemed to be bored by the process of starting new classes the spring semester, I gave them these logic puzzles to try to solve. They were given a copy of this sheet, worked in groups of three or four and after a good amount of time on each one, I read the answers aloud. I was amazed at how many they got right.
1) A customer in a restaurant ordered two cups of coffee and three doughnuts. He dunked one doughnut in one cup of coffee and two doughnuts in the other. Noticing his actions, the waitress said, “What are you doing there, sailor?” How did she know he was a sailor?
ANSWER: The customer was wearing a sailor suit.
2) A man buys five cigarettes each day. When he smokes a cigarette, he saves the butt; when he has five butts, he makes another cigarette from them. If he buys cigarettes for 25 days, how many will he be able to smoke?
ANSWER: In 25 days the man will buy 125 cigarettes. From the butts of the 125 he will make 25 more cigarettes; from those butts he will make 5 more; from those 5 butts he will make one more for a total of 156 cigarettes.
3) Hank Bent, the old trapper, has been out on his trap line in northern Minnesota with the temperature at 50 degrees below zero. He is delayed by a blizzard and, almost frozen, is barely able to stumble into his shack. The shack is extremely cold, but a fire is laid in the stove, ready to be lit. Hank looks at the fireplace, at the old lamp filled with oil, at a candle in its holder, and then at the single match that stands between him and death by freezing. Which shall he light first?
ANSWER: Hank will first light the match.
4) Jim and Bill engaged in a rifle-shooting contest, comparing their success in hitting a small target from a considerable distance. They took 50 shots each and made the same number of hits, 25. After taking a break to get a drink, they resumed their contest. They did not shoot as well this time; Jim got only three hits in 34 shots, while Bill got no more hits in 25 shots. Since Jim’s record after their break was better than Bill’s, Jim’s record for the day was clearly better than Bill’s. Or was it?
ANSWER: No, Jim’s record was not better than Bill’s but just equal. Jim shot 28 out of 84 attempts and Bill shot 25 out of 75 attempts for equal ratios of 0.333.
5) There is something fishy about the following telephone conversation. What is it?
“Good morning, Jackson Fish Packing Firm.”
“May I please talk with Mr. Fields?”
“Who is calling, please?”
“This is George Edwards.”
“I beg your pardon, but I did not catch the name.”
“George Edwards. E for evangelical, D for diversification, W for waterproof, A for antagonistic…”
“Excuse me, sir, but A for what?”
“A for antagonistic, R for reprehensible, D for developmental, S for sacroiliac – Edwards.”
“Thank you sir. Mr. Jerald is ready to talk to you.”
ANSWER: The point is that the question “A is for what?” would not be asked since the listener already knew that the letter in question was “A” and the word associated with it was not necessary to know.
