71 hard riddles with answers
Tricky riddles for adults and older teens: lateral thinking stories, classic riddles, word tricks and number traps. Reveal one answer at a time; each explains how the wording misleads.
Updated
Lateral thinking
A man lives on the 12th floor of an apartment building. Every morning he rides the elevator down to the lobby. Coming home, he rides it only to the 7th floor and takes the stairs the rest of the way, except on rainy days, when he rides all the way up. Why?
hard
He is too short to reach the button for the 12th floor. On rainy days he carries an umbrella and presses the button with it.
The story makes you think about exercise or habit. The rain is the real clue: it is the only day he has something long in his hand.
A woman walks into a coffee shop and asks for a glass of water. The server reaches under the counter, grabs a party horn and blasts it next to her ear. She says thank you and leaves without drinking anything. Why?
hard
She had hiccups. The sudden fright stopped them, so she no longer needed the water.
Asking for water reads as thirst, but people also sip water to stop hiccups. The server used a faster cure.
Romeo and Juliet are found lying motionless on the floor in a puddle of water, surrounded by broken glass. A window is open and the curtain is flapping. Nobody else has been in the room. What happened?
hard
Romeo and Juliet are goldfish. The wind blew the curtain, and the curtain knocked their bowl off a table.
The famous names make you picture people. Once they are fish, the water, the glass and the open window all fit.
The power goes out while Leo is reading a long novel at night. The room is completely dark, and he has no flashlight, candle or phone, yet he keeps reading to the end of the chapter. How?
hard
Leo is reading a braille book, so he reads with his fingertips, not his eyes.
The riddle assumes that reading needs light. Braille is read by touch, so the dark makes no difference.
A man dressed all in black walks down the middle of a country road. There are no streetlights and no moon. A car with its headlights off comes toward him, and the driver stops in plenty of time. How did the driver see him?
hard
It was daytime.
Black clothes, no streetlights and no moon all make you picture night. None of them says it is night.
A woman is resting in her hotel room when someone knocks. She opens the door to a stranger, who says, "Sorry, I thought this was my room," and walks off toward the elevator. She calls hotel security at once. Why?
hard
Nobody knocks on the door of their own room. He was checking whether the room was empty.
His apology sounds innocent, but a guest who thought the room was his would have used his key, not knocked.
A collector is offered a bronze coin stamped with the date 45 B.C. He says it is a fake without even picking it up. How does he know?
hard
No one living in 45 B.C. could know they were living "before Christ," so no real coin from that year could carry that date.
The date looks like proof of age. It is really a label that could only be given centuries later.
A woman in a small town has married more than twenty men. She has never been divorced, none of the men has died, and she has broken no law. How?
hard
She is a wedding officiant, such as a judge or a member of the clergy. She married each man to his partner.
"Married" can mean becoming someone's spouse or performing the ceremony. The riddle uses the second meaning.
Two people play five games of checkers. Each of them wins the same number of games, and none of the games ends in a draw. How?
hard
They were not playing each other. Each of them played other opponents.
Two players and five games makes you assume one match between them. Nothing in the wording says so.
A man leaves home, turns left three times, and heads back home. Two people wearing masks are waiting for him there. Who are they?
hard
The catcher and the umpire. He is running the bases in a baseball game.
"Home" and "masks" suggest a house and a robbery. In baseball, a runner turns left at each base and finishes at home plate, where the catcher and umpire wear masks.
A prisoner must leave through one of three doors. Behind the first is a room on fire. Behind the second is a deep pit. Behind the third is a room of lions that have not eaten in three years. Which door is safest?
hard
The third door. Lions that have not eaten in three years would have died long ago.
Hungry lions sound like the worst choice, but three years without food is far longer than any lion could survive.
Three doctors say that Robert is their brother. Robert says he has no brothers. Nobody is lying. How?
hard
The three doctors are Robert's sisters.
The riddle counts on you picturing the doctors as men. Nothing in the wording says they are.
Is it legal for a man to marry his widow's sister?
hard
No, because he is dead. A man only has a widow after he has died.
The question sounds like a point of family law. The word "widow" settles it before any law comes in.
A rope ladder hangs over the side of a ship at anchor, with its bottom rung just above the water. The rungs are 12 inches apart, and the tide rises 6 inches an hour. After four hours, how many rungs are under water?
hard
None. The ship floats, so it rises with the tide, and the ladder rises with it.
The numbers invite a calculation. A ship sitting on the water makes the calculation unnecessary.
How many animals of each kind did Moses take onto the ark?
hard
None. In the story, it was Noah who built the ark, not Moses.
Most people answer "two" because both names come from the same book and fit the question. The swapped name slips past unnoticed.
How much dirt is in a hole that is 3 feet deep, 3 feet wide and 3 feet long?
hard
None. A hole is empty; the dirt has been dug out.
The three measurements invite you to multiply and get 27 cubic feet. That is the size of the hole, not what is in it.
In a 100-meter sprint, you overtake the runner in last place. What place are you in now?
hard
That cannot happen. Nobody is behind the last runner, so nobody can overtake them.
The question sounds like a simple place count. To overtake someone you have to start behind them, and in a sprint nobody is behind last place.
A butcher is 6 feet tall, wears size 11 shoes and has a 34-inch waist. What does he weigh?
hard
Meat.
All the body measurements set you up to guess his weight in pounds. "Weigh" also means what a butcher does at the counter.
You are driving a bus. At the first stop, 4 people get on. At the second stop, 2 get off and 7 get on. At the third stop, 5 get off. What color are the bus driver's eyes?
hard
The same color as your eyes, because you are the driver.
The passenger numbers pull your attention to counting. The first sentence already told you who is driving.
Classic riddles
The person who makes it sells it. The person who buys it never uses it. The person who uses it never sees it. What is it?
hard
A coffin.
Each line rules out an ordinary product. A family buys a coffin, and the person who lies in it cannot see it.
The poor have it, the rich need it, and if you eat it you will die. What is it?
hard
Nothing.
Read "nothing" as the answer in every line: the poor have nothing, the rich need nothing, and if you eat nothing you starve.
What walks on four legs in the morning, two legs at noon and three legs in the evening?
hard
A person: crawling as a baby, walking upright as an adult and using a cane in old age.
Morning, noon and evening stand for the stages of a life, not the hours of one day. The third leg is the cane.
What can fly without wings, heal without medicine and never stops, even while you sleep?
hard
Time.
Each clue is a saying about time: time flies, time heals, and time keeps passing whatever you do.
What has two heads, four eyes, six legs and one tail?
hard
A person riding a horse.
No single animal fits. The rider adds one head, two eyes and two legs to the horse's one head, two eyes, four legs and tail.
The more you wash with it, the dirtier it gets. What is it?
hard
Water.
Washing usually makes things cleaner. The water carries the dirt away, so it is the one thing that ends up dirty.
What goes around and around the wood but never goes into the wood?
hard
The bark of a tree.
"Goes around" sounds like something traveling. Bark wraps the trunk on the outside and never grows into the wood itself.
Word tricks
I am a word of three letters. Add two more letters and there will be fewer. What word am I?
hard
FEW. Add E and R to make FEWER.
Adding letters sounds like it should add something. Here the longer word means a smaller number.
The first two letters of this word name a man, the first three name a woman, the first four name a brave person, and the whole word names a brave woman. What is the word?
hard
HEROINE.
HE, HER, HERO and HEROINE are all at the start of the same word, each one longer than the last.
What is 3/7 chicken, 2/3 cat and 2/4 goat?
hard
Chicago.
Take the first 3 of the 7 letters in CHICKEN (CHI), the first 2 of the 3 in CAT (CA) and the first 2 of the 4 in GOAT (GO).
What is it that, when you take away the whole, you still have some left over?
hard
WHOLESOME.
Remove WHOLE from the word WHOLESOME and SOME is left.
Nine is written IX in Roman numerals. How can you turn it into six by adding a single letter?
hard
Put an S in front to make SIX.
You expect a Roman numeral answer. The added letter turns IX into the English word SIX.
Turn me on my side and I am everything. Cut me in half and I am nothing. What am I?
hard
The number 8.
Lying on its side, 8 looks like the infinity sign. Cut across the middle, it leaves two zeros.
Remove six letters from CSIOWXLBETOTEYRS and a common word is left. What is the word?
hard
COWBOY.
"Six letters" names the letters to remove: cross out S, I, X, L, E, T, T, E, R and S, and COWBOY is left.
Which number, written as a word in English, has all its letters in alphabetical order?
hard
Forty.
F, O, R, T and Y already run in alphabetical order. The common misspelling FOURTY would break it.
Take away my first letter and I am a form of energy. Take away my first two letters and I am what you do at dinner. Mix up my last three letters and you can drink me. What word am I?
hard
WHEAT.
WHEAT without its W is HEAT. Without WH it is EAT. Its last three letters, E, A and T, rearrange into TEA.
Numbers and logic
A notebook and a pen cost $1.10 together. The notebook costs $1.00 more than the pen. How much does the pen cost?
hard
5 cents. The notebook costs $1.05.
The quick answer, 10 cents, would make the notebook $1.10 and the total $1.20. With the pen at 5 cents, $0.05 + $1.05 = $1.10.
Algae on a pond doubles its area every day. On day 30 it covers the whole pond. On which day did it cover half the pond?
hard
Day 29.
Halving 30 to 15 feels right, but the algae doubles every day, so one day before it covered the whole pond, it covered half.
The day before yesterday, Mia was 21. Next year she will turn 24. How is that possible?
hard
Today is January 1, and her birthday is December 31.
On December 30 she was 21. She turned 22 on December 31. She turns 23 this December and 24 the December after.
Three friends pay $30 for a hotel room, $10 each. The clerk realizes the room costs $25 and gives a porter $5 to return. The porter keeps $2 and gives each friend $1 back. Each friend has now paid $9, which makes $27, and the porter has $2. That adds up to $29. Where is the missing dollar?
hard
No dollar is missing. The $27 the friends paid already includes the porter's $2.
The riddle adds the porter's $2 to the $27 when it should be inside it: $27 = $25 for the room + $2 kept by the porter. Add the $3 returned to the friends and you get the original $30.
Two US coins add up to 30 cents. One of them is not a nickel. What are the two coins?
hard
A quarter and a nickel. The quarter is the one that is not a nickel.
"One of them is not a nickel" sounds like "neither is a nickel." It only rules out one of the two coins.
A trader buys a horse for $60 and sells it for $70. Then he buys it back for $80 and sells it again for $90. How much profit does he make?
hard
$20.
He spends $60 + $80 = $140 and takes in $70 + $90 = $160. Buying back at a higher price feels like a loss, but each sale earns $10.
Which letter comes next: O, T, T, F, F, S, S, E, ...?
hard
N.
These are the first letters of One, Two, Three, Four, Five, Six, Seven and Eight. Next comes Nine.
Which number comes next: 8, 5, 4, 9, 1, 7, 6, ...?
hard
10.
The numbers are in alphabetical order by their English names: eight, five, four, nine, one, seven, six, ten.
If the day before yesterday was Thursday, what day will the day after tomorrow be?
hard
Monday.
Thursday was two days ago, so today is Saturday. Two days after Saturday is Monday.
In one family, each girl has as many brothers as sisters, but each boy has twice as many sisters as brothers. How many girls and boys are there?
hard
Four girls and three boys.
Each girl has 3 brothers and 3 sisters. Each boy has 4 sisters and 2 brothers, and 4 is twice 2. Nobody counts as their own brother or sister.
A census taker asks a woman the ages of her three daughters. She says the product of their ages is 36. He cannot work it out, so she adds that their ages add up to her house number. He looks at the number and still cannot work it out. Then she says, "My oldest daughter has red hair." Now he knows. How old are the daughters?
hard
2, 2 and 9.
Of all the ways to make 36 from three ages, only 1, 6, 6 and 2, 2, 9 share a sum (13), which is why the house number did not help. "My oldest" means one daughter is older than the other two, which rules out 1, 6, 6.
You reach two doors. One leads out of the maze and the other leads back to the start. A guard stands at each door. One guard always tells the truth and the other always lies, and you do not know which is which. You may ask one guard one question. What do you ask?
hard
Ask either guard, "Which door would the other guard say leads out?" Then take the other door.
The truthful guard truthfully reports the liar's wrong answer. The liar lies about the truthful guard's right answer. Either way, the door named is the wrong one.
Why are 1990 dimes worth more than 1989 dimes?
hard
Because 1,990 dimes are one dime more than 1,989 dimes: $199.00 against $198.90.
The numbers look like years stamped on coins. Read as amounts, the larger pile is worth 10 cents more.
How many times in 24 hours do the hour hand and the minute hand of a clock point in exactly the same direction?
hard
22 times.
The quick answer is 24, once an hour. Between 11:00 and 1:00 the hands meet only once, at 12:00, so each 12 hours has 11 meetings, and a full day has 22.
There are two ducks in front of a duck, two ducks behind a duck and a duck in the middle. How many ducks are there?
hard
Three.
Three ducks in single file fit every clue: the last duck has two in front of it, the first has two behind it, and one is in the middle.
More hard riddles
Strings hide inside me, hammers strike them, and fingers choose the notes. What am I?
hard
A piano.
The source defines a piano as a stringed instrument operated from a keyboard.
Source: reference https://www.merriam-webster.com/dictionary/piano
Insert one letter into THOUGH to make a word meaning from one side to the other. Which letter?
hard
R, making THROUGH.
Inserting R after TH changes THOUGH to THROUGH, which can mean movement from one side to another.
Seasons, seconds, centuries, and minutes share one letter that decades, years, and days lack. Name it.
hard
N.
Each word in the first group contains N, while none of the three words in the second group does.
You see these words in order: YOU JUST ME. Which phrase places JUST correctly?
hard
Just between you and me.
JUST appears between YOU and ME, so its placement spells out the phrase.
Looking at a portrait, Arun says, "I have no siblings, but this person's father is my father's son." Who is pictured?
hard
Arun's child. With no siblings, "my father's son" means Arun.
Because Arun has no siblings, his father's son can only be Arun, making the pictured person's father Arun.
One box holds only apples, one only oranges, and one a mix. Their labels APPLES, ORANGES, and MIXED are all wrong. You may draw one fruit from one box. Which box should you draw from first?
hard
Draw from the box labeled MIXED. Its fruit reveals that box's true single-fruit label, and the two remaining wrong labels then determine each other.
Because every label is wrong, the MIXED-labeled box contains only one fruit type. One draw identifies it, and the remaining false labels force the other assignments.
Exactly one key opens a box. Key A does not open it. If Key B opens it, then Key C also opens it. Which key opens the box?
hard
Key C. B cannot open it because that would make C open it too, violating "exactly one." A is ruled out.
A is excluded directly. B would force both B and C to work, contradicting exactly one, so only C remains.
Find the smallest positive whole number equal to seven times the sum of its digits.
hard
21, because 2 + 1 = 3 and 7 x 3 = 21.
Testing positive multiples of 7 in order, 21 is the first whose digit sum, 3, becomes the number when multiplied by 7.
Continue the description sequence: 1, 11, 21, 1211, 111221. What comes next?
hard
312211, because 111221 contains three 1s, two 2s, and one 1.
Reading 111221 in groups gives three 1s, two 2s, and one 1, encoded as 31 22 11.
Arrange six equal sticks so they form four equal triangles, without breaking or overlapping a stick. What shape solves it?
hard
A tetrahedron. Its six edges make four triangular faces.
A tetrahedron has exactly six edges and four congruent triangular faces, so each stick becomes one edge.
Draw a square and both diagonals. Counting every size, how many triangles are outlined?
hard
Eight triangles: four small triangles and four large half-square triangles.
The diagonals create four small central triangles, and each pair of adjacent small triangles forms one of four larger half-square triangles.
Imagine a standard seven-segment display showing 8. Remove only the upper-right segment. Which digit remains?
hard
6.
The source states that the upper-right segment is off for 6 and shows the standard digit segment logic.
Source: reference https://websites.umich.edu/~mconger/2010/Clock/index.html
Paint every face of a cube, then cut it into 27 equal smaller cubes. How many small cubes have exactly two painted faces?
hard
12.
A 3 by 3 by 3 cube has one non-corner cube at the middle of each of its 12 edges, and each of those touches exactly two outer faces.
A leathery coat guards rubies packed tight; open my chamber for seeds red and bright. What am I?
hard
A pomegranate.
The source defines a pomegranate as a fruit with a tough rind and many-seeded pulp.
Source: reference https://www.merriam-webster.com/dictionary/pomegranate
A beetle starts at the lower-left corner of a square. It crosses diagonally, moves one edge counterclockwise, then crosses diagonally again. Which corner does it reach?
hard
The lower-right corner.
The first diagonal reaches upper right, the edge move reaches upper left, and the second diagonal reaches lower right.
A square table has one seat on each side. Niko sits opposite Uma. Pia sits immediately clockwise from Niko. What occupies the seat immediately clockwise from Uma?
hard
Nothing. It is the unoccupied fourth seat.
Opposite seats are two steps apart. Pia fills the clockwise seat after Niko, leaving the clockwise seat after Uma unoccupied.
Three signals begin together. They repeat every 4, 6, and 9 minutes. After how many minutes do all three next occur together?
hard
36 minutes.
Thirty-six is the smallest positive multiple shared by 4, 6, and 9.
Five speakers each use 4 minutes, with a 1-minute changeover between speakers. How long from the first start to the final finish?
hard
24 minutes.
The talks use 20 minutes and the four changeovers use 4 more.
A timer shows 10 for one second, then 9 for one second, continuing through 0. How long does it display a number?
hard
11 seconds.
It displays eleven values, from 10 through 0 inclusive, for one second each.
A voice says, "Visiting relatives can be tiring." What are the two possible sources of the tiredness?
hard
The act of visiting relatives, or relatives who are visiting.
Visiting can describe an activity or the relatives.
Mina says, "I almost answered every question." Give the two possible meanings.
hard
She answered nearly all of them, or she came close to answering each one but answered none.
Almost can apply to the whole set or separately to the act of answering each question.
Plan the round and team scores
8 turns × 60 seconds = 8 minutes of play, plus instructions and breaks.
60
These are adjustable house rules. Pause whenever the group needs more time.
Team 1: 0
Team 2: 0
Use this set with a group
Read a prompt, allow thinking time, then invite an answer or a pass. For a timed round, choose a turn length before starting. A host can keep the printed answers out of view until the round ends.