🎓 Hard riddles for adults with answers
Wordplay, logic and a bit of math. Some of these look simple and aren't - check your answer before you open ours.
I turn once, and what is out will not get in. I turn again, and what is in will not get out. What am I?
💡 Hint
Think of a door.
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A key
What five-letter word sounds the same when you remove its first, third and last letters?
💡 Hint
Say the two remaining letters out loud.
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"Empty" - remove E, P and Y and you're left with "MT," which sounds like "empty."
A man stands on one side of a river and his dog on the other. He calls the dog, and it crosses without getting wet, without a bridge and without a boat. How?
💡 Hint
Think about the season.
Show the answer
The river was frozen.
What English word has three double letters in a row?
💡 Hint
Someone who keeps the accounts.
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Bookkeeper (oo, kk, ee)
Multiply me by any number and the answer is always the same. What number am I?
💡 Hint
It swallows everything.
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Zero
What can you find in the middle of nowhere?
💡 Hint
Spell it out.
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The letter H
A clock takes 5 seconds to strike six o'clock. How long does it take to strike twelve?
💡 Hint
Count the gaps between the strikes, not the strikes.
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11 seconds. Six strikes have 5 gaps, so each gap is 1 second. Twelve strikes have 11 gaps.
What letter comes next: O, T, T, F, F, S, S, E, ...?
💡 Hint
Count out loud.
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N - they are the first letters of One, Two, Three... and Nine comes next.
A woman has 7 daughters, and each daughter has a brother. How many children does she have?
💡 Hint
Do they each need their own brother?
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8 - seven daughters and one son they all share.
Which is correct: "The yolk of the egg is white" or "The yolk of the egg are white"?
💡 Hint
Forget the grammar.
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Neither - egg yolks are yellow.
Two in a corner, one in a room, zero in a house, but one in a shelter. What am I?
💡 Hint
Look at the spelling of each place.
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The letter R
You're on a game show with three doors: a car behind one, goats behind the other two. You pick door 1. The host, who knows where the car is, opens door 3 to show a goat. Should you switch to door 2?
💡 Hint
What were the chances your first pick was right?
Show the answer
Yes. Your first pick wins only 1 time in 3. The host always shows a goat, so the other closed door holds the car the other 2 times in 3. Switching doubles your chances.
Using four 4s and any basic math signs, make the number 7.
💡 Hint
Two 4s can make a 1.
Show the answer
(4 + 4) - (4 ÷ 4) = 8 - 1 = 7. Another way: 44 ÷ 4 - 4 = 11 - 4 = 7.
What number, written as an English word, has all its letters in alphabetical order?
💡 Hint
It's between 30 and 50.
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Forty (F, O, R, T, Y)
Rearrange the letters of "NEW DOOR" to make one word.
💡 Hint
Take the question literally.
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"One word"
If two's company and three's a crowd, what are four and five?
💡 Hint
Just add.
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Nine
Turn me on my side and I am everything. Cut me in half and I am nothing. What am I?
💡 Hint
I'm a number.
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The number 8. On its side it's the infinity sign; cut in half it's two zeros.
I'm a three-digit number. My tens digit is 5 more than my ones digit, and my hundreds digit is 8 less than my tens digit. What number am I?
💡 Hint
Start with the tens digit - how big must it be?
Show the answer
194. The hundreds digit must be at least 1, so the tens digit is 9, the ones digit is 4 and the hundreds digit is 1.
How many squares of any size are on a standard 8 × 8 chessboard?
💡 Hint
Don't forget the bigger squares.
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204. There are 64 squares of 1×1, 49 of 2×2, 36 of 3×3 and so on down to one 8×8: 64 + 49 + 36 + 25 + 16 + 9 + 4 + 1 = 204.
Imagine you're in a room with no doors or windows, and it's slowly filling with water. How do you get out?
💡 Hint
Read the first word again.
Show the answer
Stop imagining.
A rope ladder hangs over the side of a ship. The rungs are a foot apart and 10 rungs are above the water. The tide rises 4 feet. How many rungs are above the water now?
💡 Hint
What happens to the ship when the tide comes in?
Show the answer
Still 10. The ship floats, so it rises with the tide along with the ladder.
What is 3/7 chicken, 2/3 cat and 2/4 goat?
💡 Hint
Take the letters, not the animals.
Show the answer
Chicago (CHI + CA + GO)
When the day after tomorrow is yesterday, today will be as far from Sunday as today was from Sunday when the day before yesterday was tomorrow. What day is it today?
💡 Hint
Work out each "day" as today plus or minus a number.
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Sunday. The first day described is 3 days after today, the second is 3 days before today. They are the same distance from Sunday only if today is Sunday.
What has an eye, but can't see, and is the strongest wind of all?
💡 Hint
It forms over warm oceans.
Show the answer
A hurricane
Quick answers
I turn once, and what is out will not get in. I turn again, and what is in will not get out. What am I?
A key
What five-letter word sounds the same when you remove its first, third and last letters?
"Empty" - remove E, P and Y and you're left with "MT," which sounds like "empty."
A man stands on one side of a river and his dog on the other. He calls the dog, and it crosses without getting wet, without a bridge and without a boat. How?
The river was frozen.
What English word has three double letters in a row?
Bookkeeper (oo, kk, ee)
Multiply me by any number and the answer is always the same. What number am I?
Zero