Riddle: It's always 1 to 6, it's always 15 to 20, it's always 5, but it's never 21, unless it's flying. What is it?
Answer: The answer is: a dice. An explanation: "It's always 1 to 6": the numbers on the faces of the dice, "it's always 15 to 20": the sum of the exposed faces when the dice comes to rest after being thrown, "it's always 5": the number of exposed faces when the dice is at rest, "but it's never 21": the sum of the exposed faces is never 21 when the dice is at rest, "unless it's flying": the sum of all exposed faces when the dice is flying is 21 (1 + 2 + 3 + 4 + 5 + 6).
Difficult Riddles: It's always 1 to 6,  it's always 15 to 20,  it's always 5,  but it's never 21,  unless it's flying.
What is it? Riddle Meme.
Riddle: A boy leaves home in the morning to go to school. At the moment he leaves the house he looks at the clock in the mirror. The clock has no number indication and for this reason, the boy makes a mistake in interpreting the time (mirror-image). Just assuming the clock must be out of order, the boy cycles to school, where he arrives after twenty minutes. At that moment the clock at school shows a time that is two and a half hours later than the time that the boy saw on the clock at home. What time is it?
Answer: The difference between the real time and the time of the mirror image is two hours and ten minutes (two and a half hours, minus the twenty minutes of cycling). Therefore, the original time on the clock at home that morning could only have been five minutes past seven: The difference between these clocks is exactly 2 hours and ten minutes (note that also five minutes past one can be mirrored in a similar way, but this is not in the morning!). Conclusion: The boy reaches school at five minutes past seven plus twenty minutes of cycling, which is twenty-five minutes past seven!...
Riddle: I run, it runs, I stop, it runs What it it?
Answer: My watch.
I run, it runs, I stop, it runs
What it it?  Riddle Meme.
Riddle: How can this be true? Have a look at the picture. All the lines are straight, the shapes that make up the top picture are the same as the ones in the bottom picture so where does the gap come from?
Answer: The green triangle has dimensions 2 x 5 and gradient 2 / 5 = 0.4 The red triangle has dimensions 3 x 8 and gradient 3 / 8 = 0.375 Hence the gradient of the green triangle is greater than that of the red triangle.
Riddle: Ben walked into a hardware store and asked the price of some items. The salesman said: One costs $1, Eight costs $1, Seventeen cost $2, One hundred four costs $3 and One thousand seventy two costs $4. What was Ben buying?
Answer: Ben was buying home address numbers and they cost $1 per digit.
Ben walked into a hardware store and asked the price of some items. The salesman said: One costs $1, Eight costs $1, Seventeen cost $2, One hundred four costs $3 and One thousand seventy two costs $4. What was Ben buying? Riddle Meme.
Riddle: An item is made from lead blanks in a lathe shop. Each blank suffices for 1 item. Lead shavings accumulated for making 6 items can be melted and made into a blank. How many items can be made from 36 blanks?
Answer: From 36 blanks there are 36 items made. The lead shavings are enough to make 6 blanks. Which make 6 more items. But don't stop here. The new shavings are good for 1 more item. Total: 43.
Riddle: Carl is trying to find solutions to a geometric puzzle. He has a square plot of land that he needs to reserve 1/4 for himself and divide the remaining 3/4 equally and in similar shape, among his 4 children. There are two possible solutions. Can you solve the puzzle?
Answer: Solution #1 - Squares First, Carl divides his as to reserve to himself one-fourth in the form of a square. Geometric Puzzle #1 Then, Carl takes the remaining 3/4 shape and scales it down by 1/4.  He then, multiplies the shape into 4 identically shaped pieces, and aranges them so that they fit into the original 3/4 shape. Geometric Puzzle #1 Solution 1 Solution #2 - Rectangles First, create a triangle that is 1/4 the size of the square. Now, with straight lines, create two squares. Proceed to disect the two squares with horizontal lines creating 4 triangles. Then, disect one of the resultuing triangles from each square.  The shape of land for each of his four children is divided evenly and is the same shape.
Riddle: Jack has 8 bricks 7 of them weights the same amount and one is slightly heavier. Using a balance scale, how can Jack find the heavier brick in two weighings?
Answer: First he split them in to piles of 3, 3, and 2 bricks. Then he weighs both groups of 3 with each other. If they balance he knows the brick is one of the 2 unweighed bricks and he can weigh them to find the heaver one. If the the stacks of 3 bricks do not balance, he will weigh 2 of the 3 bricks. If they balance he will know the brick left unweighed is heavier, or if they do not balance, he will find the heavier one.
Riddle: Two travellers spend from 12 o'clock to 6 o'clock walking along a level road, up a hill and back again. Their pace is 4 mph on the level, 3 mph uphill, and 6 mph downhill. How far do they walk and at what time do they reach the top of the hill?
Answer: 24 miles half past three.
Riddle: A car's odometer shows 72927 miles, a palindromic number. What are the minimum miles you would need to travel to form another?
Answer: 110 miles. (73037)