Riddles
I am not alive, but I grow; I don't have lungs, but I need air; I don't have a mouth, but water kills me. What am I?
Fire
What is the smallest country in the world by land area?
Vatican City
What is the next number in the following sequence: 1, 11, 21, 1211, 111221, 312211?
Answer: 13112221 (the sequence is generated by describing the previous term, hence the next term is "one 3, one 1, two 2's, two 1's").
You have 12 coins, one of which is counterfeit and slightly lighter than the others. You also have a balance scale. How can you identify the counterfeit coin using the scale only three times?
Divide the coins into three groups of four. Weigh any two groups against each other. If they balance, then the counterfeit coin is in the third group. If they don't balance, then the counterfeit coin is in the lighter group. Take two coins from that group and weigh them against each other. If they balance, then the third coin is the counterfeit. If they don't balance, then the lighter coin is the counterfeit.
How many states are there in the United States?
50
The more you take, the more you leave behind. What am I?
Footsteps
In which year did the Chernobyl nuclear disaster occur?
1986
I am a three-digit number. My tens digit is five times my ones digit. My hundreds digit is three less than my tens digit. What number am I?
195
A man is looking at a photograph of someone. His friend asks who it is. The man replies, "Brothers and sisters, I have none. But that man's father is my father's son." Who is in the photograph?
The man in the photograph is the man's son.
What is the capital city of France?
Paris
I am taken from a mine, and shut up in a wooden case, from which I am never released, and yet I am used by almost every person. What am I?
Pencil lead / graphite
What is the only continent in the world that is also a country?
Australia
Two fathers and two sons went fishing one day. They managed to catch one fish each, but when they returned home they only had three fish. How is this possible?
The fishing party consisted of a grandfather, his son, and his grandson. Therefore, there were only three individuals, and thus only three fish caught.
There are six eggs in a basket. Six people each take one egg. How can it be that one egg is left in the basket?
The last person took the basket with the last egg still in it.
What is the chemical symbol for gold?
Au
I am not alive, but I can die. I don't have wings, but I can fly. I don't have eyes, but I can see. What am I?
Imagination
Which composer wrote the famous opera "The Marriage of Figaro"?
Mozart
What is the largest three-digit number that, when divided by the sum of its digits, equals 9?
Answer: 864 (864 divided by 9 equals 96, which is the sum of the digits in 864).
You have two jars, one with red marbles and one with blue marbles. Each jar is labeled, but all the labels are incorrect. How can you determine which jar contains which colored marbles by removing only one marble from one of the jars?
Take a marble from the jar labeled "blue and red" (since the label is incorrect, the jar actually contains either all blue or all red marbles). If it is blue, then that jar must be the blue jar, and the other jar is the red jar. If it is red, then the jar from which you took the marble must be the red jar, and the other jar is the blue jar.
What is the highest mountain in Africa?
Mount Kilimanjaro
I am not alive, but I can die. I don't have a mouth, but I can scream. What am I?
Waterfall
Which ancient civilization was known for building Machu Picchu?
The Inca Civilization
A farmer wants to cross a river with a fox, a chicken, and a sack of grain. The boat is small and can only hold the farmer and one other item at a time. If the farmer leaves the fox and chicken alone together, the fox will eat the chicken. If he leaves the chicken and grain alone together, the chicken will eat the grain. How can the farmer get all three items safely across the river?
The farmer must take the chicken across first, leaving the fox and grain alone together on the original side of the river. He then takes the fox across, but brings the chicken back with him. He then takes the grain across and leaves it with the fox, before returning to get the chicken and bringing it across the river.
You have three light switches in a room, each of which controls one of three lamps in another room. You cannot see the lamps from the room with the switches, and you can only go to the other room once. How can you determine which switch controls which lamp?
Turn on the first switch and leave it on for a few minutes. Turn it off and turn on the second switch. Enter the other room. The lamp that is on is controlled by the second switch. Feel the other two lamps; the one that is still warm is controlled by the first switch, and the one that is cool is controlled by the third switch.
What is the name of the longest river in South America?
Amazon