- My daughter has many sisters. She has as many sisters as she has brothers. Each of her brothers has twice as many sisters as brothers. How many sons and daughters do I have?
Four daughters and three sons.
- A man wanted to enter an exclusive club but did not know the password that was required. He waited by the door and listened. A club member knocked on the door and the doorman said, "twelve." The member replied, "six" and was let in. A second member came to the door and the doorman said, "six." The member replied, "three" and was let in. The man thought he had heard enough and walked up to the door. The doorman said, "ten" and the man replied, "five". But he was not let in. What should have he said?
The man had to reply the number of characters in the word the Doorman was asking. He should have replied "Three" instead of "Five".
- Three people picked 65 apples altogether. At the first tree they each picked the same number of apples. At the second tree they each picked 3 times as many as they picked at the first tree. When they finished at the third tree, the group had 5 times as many apples as they had when they started at that tree. At the fourth tree the group picked just 5 apples. How many apples did each person pick at the first tree?
- There are 20 pieces of bread to divide among 20 people. A man eats 3 pieces, woman eats 2 pieces and a child eats half piece of bread. Tell the correct combination of men, women and children so that they are 20 people in total and everyone gets the bread. Note that a man cannot eat less than 3 or more than 3. A woman cannot eat less than 2 or more than 2 and the child cannot eat less than half or more than half piece of the bread. You have to tell there are how may are men, women and children in those 20 people.
There are 5 women, 1 man and 14 children.
- Here is a series of numbers. What is the next number in the sequence?
The next number in the sequence is 1113213211, because the rule for creating the next number is to simply describe the previous number. For example, you start of with 1, with is simply one 1, so the next number is 11. Now you have two 1's, so the next number is 21. Now you have one 2 and one 1, so the next number is 1211. The solution is to simply continue describing the previous number using only numbers.
- An 18-wheeler is crossing a 4 kilometer bridge that can only support 10,000 kilograms and that's exactly how much the rig weighs. Halfway across the bridge a 30 gram sparrow lands on the cab, but the bridge doesn't collapse. Why not?
Since the bridge is 4 kilometers long, the halfway point would be 2 kilometers. The 18-wheeler would have used much more than 30g of fuel to drive 2 kilometers.
- You have 12 black socks and 12 white socks mixed up in a drawer. It's early in the morning and you don't have any light to see the colors. How many socks must you pull out (blindly) to be sure of getting a matching pair?
3 socks. If the first sock is black, the second one could be black, in which case you have a matching pair. If the second sock is white, the third sock will be either black and match the first sock, or white and match the second sock.
- I was visiting a friend one evening and remembered that he had three daughters. I asked him how old they were. "The product of their ages is 72," he answered. Quizzically, I asked, "Is there anything else you can tell me?" "Yes," he replied, "the sum of their ages is equal to the number of my house." I stepped outside to see what the house number was. Upon returning inside, I said to my host, "I'm sorry, but I still can't figure out their ages." He responded apologetically, "I'm sorry, I forgot to mention that my oldest daughter likes strawberry shortcake." With this information, I was able to determine all of their ages. How old is each daughter? You have enough information to solve the puzzle.
3, 3, and 8. The only groups of 3 factors of 72 to have non-unique sums are 2, 6, 6 and 3, 3, 8 (both add up to 14). The presence of a single oldest child eliminates 2,6,6.
- You're riding a horse. To the right of you is a cliff and in front of you is an elephant going the same pace as you and you can't overtake it. To the left of you is a hippo running at the same speed and behind you is a lion chasing you. How do you get to safety?
Get off the merry-go-round.
- A cube of side 4cm is painted with 3 colors red, blue and green in such a way that opposite sides are painted in the same color. This cube is now cut into 64 cubes of equal size.
How many have at least two sides painted in different colors.
How many cubes have only one side painted.
How many cubes have no side painted.
Cubes that have at least two sides painted in different colors are 24 + 8 = 32.
Cubes that have only one side painted are 24.
Cubes that have no side painted = 8.
Cubes that have exactly one side not painted = 0.