Brain Teasers

1. One train leaves from New York City heading towards Los Angeles at 100 mph. Three hours later, a train leaves from LA heading towards NYC at 200 mph. Assume there is exactly 2000 miles between LA and NYC. When they meet, which train is closer to NYC?

2. What number is two-thirds of one-half of one-fourth of 240?

3. If today is Monday, what is the day after the day before the day before tomorrow?

4. Mary promised Kay today that she would tell Kay a big secret on the day before four days from the day after tomorrow. If today is Saturday the 12th, on what day and date will Mary tell Kay her big secret?

5. If some coffee is 97% caffeine-free, how many cups of it would one have to drink to get the amount of caffeine in a regular cup of coffee?

6. An adult and a child are walking down the street. The child is the adult's son, but the adult is not the child's father. How is this possible?

7. What's in seasons, seconds, centuries and minutes but not in decades, years, or days?

8. One pencil can be made from four nubs of used pencils. If a man uses 16 pencils down to nubs, how many more pencils can he make?

9. Amoebas reproduce by splitting in two. An amoeba that does so every minute is placed in a jar at exactly 10 o'clock in the morning. At 12:00 noon the jar is full. At what time is the jar half full?

10. A prisoner is told "If you tell a lie we will hang you; if you tell the truth we will shoot you." What can he say to save himself?

11. Looking at a picture a man says, "Brothers and sisters I have none, but that man's father is my father's son." Whose picture is it?

12. If you can buy 1 for $1.00, 12 for $2.00, and 150 for $3.00, what are you buying?

13. I have two coins making 55 cents, but one is not a nickel. How can that be?

14. The two sons of an Arab sheik were each overwhelmingly proud of their own horses. When the sheik died, he left instructions that they have a race and the one whose horse loses the race would inherit his fortune. They started the race at full speed but gradually slowed down and stopped not knowing what to do. A passing traveler heard their story and advised them. They jumped on the horses and raced as fast as they could to the finish line. What was the advice?

15. What is the next number in the sequence - 77, 49, 39, 18?

16. Why are 1977 dollars worth more than 1976 dollars?

17. What is the eleven letter word that all Yale graduates spell incorrectly?

18. A clock chimes once at the quarter, half, and three-quarters the hour. When does it strike one time, five times in a row at fifteen minute intervals?

19. If someone finds an old coin bearing a date 47 BC and offers to sell it to you for one dollar how much would you pay?

20. In the United States is it legal for a man to marry his widow's sister?

21. How much dirt is there in a hole that measures two feet by three feet by four feet?

22. How many months have 28 days in them?

23. Which is correct - eight and eight IS fifteen or eight and eight ARE fifteen?

24. A 10-foot ladder hangs over the side of a boat with the bottom rung at the surface of the water. There is one foot between the rungs and the tide goes up at a rate of 6 inches per hour. How long until three rungs are covered?

25. Mr. And Mrs. Smith have six daughters and each daughter has a brother. How many people are in the family?

26. Two fathers and two sons each shot a duck, and none of them shot the same duck. Only three ducks were shot. Why?

27. We all know there are 12 one-cent stamps in a dozen, but how many two-cent stamps are there in a dozen?

28. How long will an eight-day clock run without winding?

29. A boat will carry only 200 pounds. How can a man weighing 200 pounds and his two sons, each weighing 100 pounds use the boat to cross the river?

30. A bottle and a cork together cost $1.50. The bottle costs a dollar more than the cork. How much does each cost?

31. Take two apples from three apples and what have you got?

32. What do the following represent? A) 1001 = A.N. B) 54 = C. in the D. (with the J.'s) C) 29 = D. in F. in L.Y. D) 24 = H. in a D. E) 13 = S. on the A.F. F) 26 = L. of the A.

33. From what singular noun can you remove an S and make it a plural noun?

34. There are three errers in the statement of this problem. You must detect all of them to receive full credit.

35. A King wanted to get rid of the Prime Minister so he told three judges that he would put two slips of paper in a hat and have the Prime Minister draw one of them. He said that one slip would be marked "Go" and the other "Stay," but he cheated and marked both of them "Go." The Prime Minister suspected that the King would cheat so how did he draw one slip and manage to stay?