Riddle 1 You have 8 balls of equal size. 7 of them weigh the same, but one is heavier. You have a balance scale. What is the minimum number of weighings needed to find the heavier ball?
Riddle 2 A man has to get a wolf, a goat, and a cabbage across a river. His boat can carry only himself and one other at a time. The wolf cannot be left alone with the goat, and the goat cannot be left with the cabbage. How does he do it?
Riddle 3 A car travels 60 km at 30 km/h and another 60 km at 60 km/h. What is the average speed of the car for the whole journey?
Riddle 4 You are in a room with 3 light switches. In the next room, there are 3 light bulbs (all off). You may enter the room with bulbs only once. How can you find out which switch controls which bulb?
Riddle 5 A man is looking at a person’s photograph. His friend asks, “Who is it?” The man replies: “Brothers and sisters, I have none. But this man’s father is my father’s son.” Who is in the picture?
Riddle 6 I am a two-digit number. When you read me from right to left, I get larger and the numbers should be consecutive. When you add my digits, the sum is 13. What number am I?
Riddle 7 Three ants are sitting at the corners of a triangle. Each ant randomly chooses a direction and starts walking along the edge. What is the probability that none of them collide?
Riddle 8 I’m taken from a mine and shut up in a wooden case, from which I am never released, and yet I am used by almost everybody. What am I?
Riddle 9 I’m light as a feather, yet the strongest person can’t hold me for five minutes. What am I?
Riddle 10 You need to measure exactly 4 liters of water using only a 5-liter and a 3-liter jug. How do you do it?
Riddle 11 I have cities, but no houses. I have mountains, but no trees. I have water, but no fish. What am I?
Riddle 12 I have a face but no eyes. I have hands but no arms. I have a ticking sound but no heart. You look at me to solve a problem involving time. What am I?
Riddle 13 A have a bed but I never sleep. I have a mouth but I never speak. What I am
Riddle 14 Forward I am heavy, backward I am not.
Riddle 15 Break me and I’ll continue to work; look at me and I may lie.