Brain teasers with answers
These brain teasers with answers are made for curious minds of every age, from class 5 students to grandparents who love a good puzzle. You will find quick logic tricks, number brain teaser puzzles, clock and calendar puzzles, and some genuinely hard ones to finish with.
Every answer is hidden until you tap Show answer, and each one comes with a short working so you can see exactly why it is right. Try to solve each puzzle before peeking, and keep a pen and paper close for the number ones.
Quick brain teasers for everyone
Riddle 1
You are running a school race and you overtake the runner in second place. What position are you in now?
Show answer
Second placeYou took the place of the person who was second, so you are now second, not first.
Riddle 2
A teacher had 32 notebooks to correct. All but 7 got soaked in the rain on the way home. How many notebooks stayed dry?
Show answer
7 notebooks"All but 7" means every notebook except 7 got wet, so exactly 7 stayed dry.
Riddle 3
Riya has 3 sisters. Each of her sisters has exactly 1 brother. How many children are there in the family?
Show answer
5 childrenThe 3 sisters share the same single brother, so the family is Riya, her 3 sisters and 1 brother: 1 + 3 + 1 = 5.
Riddle 4
5 cooks make 5 rotis in 5 minutes. How long will 50 cooks take to make 50 rotis?
Show answer
5 minutesEach cook makes 1 roti in 5 minutes. With 50 cooks working together, each still makes 1 roti in the same 5 minutes.
Riddle 5
Seema plants a tree at the very start of a 50 metre road and then one every 5 metres up to the very end. How many trees does she plant?
Show answer
11 treesThere are 50 / 5 = 10 gaps, and a row of 10 gaps has one more tree than gaps, so 10 + 1 = 11.
Riddle 6
What can you hold in your left hand but never in your right hand?
Show answer
Your right elbowYour left hand can grip your right elbow easily, but your right hand can never reach and hold its own elbow.
Riddle 7
Using one letter, how can you add something to 9 and turn it into 6?
Show answer
Add S to IX to make SIXWrite 9 in Roman numerals as IX. Put an S in front and it reads SIX.
Riddle 8
Mehul threw a ball as hard as he could. It came straight back to him without hitting a wall, a bat or anyone. How?
Show answer
He threw it straight upA ball thrown straight up stops, turns around under gravity and falls back to the thrower.
Riddle 9
Rearrange the letters of LISTEN to make a word that means no sound at all.
Show answer
SILENTLISTEN and SILENT use exactly the same six letters: L, I, S, T, E, N.
Riddle 10
Which is the odd one out: cow, goat, sparrow, buffalo?
Show answer
SparrowThe sparrow is the only bird. The cow, goat and buffalo are all four legged farm animals.
Number brain teaser puzzles
Riddle 11
A notebook and a pen cost 110 rupees together. The notebook costs 100 rupees more than the pen. What does the pen cost?
Show answer
5 rupeesIf the pen is p, the notebook is p + 100, so 2p + 100 = 110 and p = 5. The quick guess of 10 rupees gives a total of 120.
Riddle 12
Find the next number in this line: 2, 6, 12, 20, 30, ?
Show answer
42Each number is n x (n + 1): 1x2, 2x3, 3x4, 4x5, 5x6, so the next is 6x7 = 42.
Riddle 13
Find the next number: 3, 5, 9, 17, 33, ?
Show answer
65Each number is double the previous one minus 1: 33 x 2 - 1 = 65.
Riddle 14
Which letter comes next in this line: A, C, F, J, O, ?
Show answer
UThe gaps grow by one each time: +2, +3, +4, +5, so the next jump is +6. O is the 15th letter and 15 + 6 = 21, which is U.
Riddle 15
Mohan read one third of a storybook on Monday and one quarter of it on Tuesday. He still has 50 pages left. How many pages does the book have?
Show answer
120 pagesHe read 1/3 + 1/4 = 7/12 of the book, so 5/12 is left. If 5/12 is 50 pages, the whole book is 50 x 12 / 5 = 120.
Riddle 16
A father is 30 years older than his son. In 5 years he will be exactly 3 times as old as his son. How old is the son today?
Show answer
10 years oldIf the son is s, then s + 35 = 3(s + 5), which gives 2s = 20 and s = 10. In 5 years they will be 15 and 45.
Riddle 17
The average of 5 numbers is 20. When one number is taken away, the average of the other 4 becomes 18. Which number was removed?
Show answer
28The 5 numbers add up to 5 x 20 = 100 and the remaining 4 add up to 4 x 18 = 72, so the removed number is 100 - 72 = 28.
Riddle 18
I am a two digit number. My digits add up to 9, and if you swap my digits I grow by 27. What number am I?
Show answer
36Swapping digits changes a number by 9 times the difference of its digits, so the digits differ by 3 and add to 9. That gives 3 and 6, and 63 - 36 = 27.
Riddle 19
Use exactly six 9s and any maths signs you like to make 100.
Show answer
99 + 99/99 = 10099/99 is 1, and 99 + 1 = 100. Count the nines: two in each of the three 99s, six in total.
Riddle 20
Using only plus signs, how can eight 8s add up to 1000?
Show answer
888+88+8+8+8888 + 88 = 976, and adding three single 8s gives 976 + 24 = 1000, using eight 8s in all.
Logic brain teasers with answers
Riddle 21
If the day after tomorrow is Sunday, what day was the day before yesterday?
Show answer
WednesdayIf the day after tomorrow is Sunday, today is Friday. Two days before Friday is Wednesday.
Riddle 22
Pointing at a photo of a boy, Neha says: His mother is the only daughter of my mother. How is Neha related to the boy?
Show answer
She is his motherThe only daughter of Neha's mother is Neha herself, so the boy's mother is Neha.
Riddle 23
In a race of five, Ekta came first. Chiku finished before Asha, Asha before Bunty, and Dolly after Bunty. Who came last?
Show answer
DollyEkta is first, and the chain Chiku, Asha, Bunty, Dolly fills places 2 to 5, so Dolly is last.
Riddle 24
Asha, Bilal and Chitra wear red, blue and green shirts, one each. Asha is not in red and Bilal wears blue. What colour is Chitra wearing?
Show answer
RedBilal has blue, so Asha (not red) must have green, which leaves red for Chitra.
Riddle 25
A drawer holds plenty of red, blue and green socks, all mixed up. In the dark, what is the fewest socks you must pull out to be sure of a matching pair?
Show answer
4 socksWith 3 colours you could pull one of each and still have no pair. The 4th sock must match one of the first three.
Riddle 26
Meena is 12th from the top and 18th from the bottom in her class list. How many students are in the class?
Show answer
29 studentsCounting from both ends counts Meena twice, so the total is 12 + 18 - 1 = 29.
Riddle 27
Today is Wednesday. What day of the week will it be exactly 100 days from today?
Show answer
Friday100 days is 14 full weeks plus 2 days, since 100 = 14 x 7 + 2. Two days after Wednesday is Friday.
Riddle 28
Three boxes are labelled Apples, Oranges and Mixed, and every label is wrong. You may take out one fruit from one box. Which box do you pick from to fix all the labels?
Show answer
The box labelled MixedThat box cannot be mixed, so one fruit tells you what it holds. The other two wrong labels can then only be swapped one way.
Riddle 29
Two mothers and two daughters bought 3 mangoes and each of them got exactly one whole mango. How?
Show answer
Grandmother, mother and daughterThere are only three people: a grandmother, her daughter and her granddaughter. The middle one is both a mother and a daughter.
Riddle 30
A girl has as many brothers as sisters, but each of her brothers has only half as many brothers as sisters. How many children are there?
Show answer
7 children (4 girls, 3 boys)With 4 girls and 3 boys, each girl sees 3 sisters and 3 brothers, and each boy sees 2 brothers and 4 sisters, which is half.
Time, clock and calendar brain teasers
Riddle 31
The school clock shows exactly 4:20. What is the angle between its hour hand and minute hand?
Show answer
10 degreesThe minute hand points at 4, which is 120 degrees. The hour hand has moved a third of the way from 4 to 5, so it is at 120 + 10 = 130 degrees, a gap of 10.
Riddle 32
What is the date exactly 100 days after 1 January 2025?
Show answer
11 April 2025January has 31 days, February 28 and March 31, which make 90 days to 1 April. Ten more days lands on 11 April.
Riddle 33
You see a wall clock in a mirror and it seems to show 2:30. What is the real time?
Show answer
9:30For a mirror image, subtract the shown time from 12:00 (11:60 to make it easy): 11:60 - 2:30 = 9:30.
Riddle 34
Between noon and midnight, how many times do the hour hand and minute hand of a clock point in exactly the same direction?
Show answer
11 timesThe hands meet every 12/11 hours, which is about 65 minutes 27 seconds. In 12 hours that happens 11 times.
Riddle 35
A night train leaves at 11:50 pm and the journey takes 7 hours 25 minutes. When does it arrive?
Show answer
7:15 am10 minutes takes it to midnight, and the remaining 7 hours 15 minutes brings it to 7:15 am.
Riddle 36
News of a holiday doubles the number of people who know it every hour. By 8 pm all 1024 people in a colony know. At what time did half the colony know?
Show answer
7 pmBecause the count doubles each hour, half of 1024 (that is 512) knew exactly one hour earlier, at 7 pm.
Riddle 37
Ravi was born on 29 February 2016. By his 10th birthday in 2026, how many times could he celebrate on 29 February itself?
Show answer
2 times29 February only comes in leap years. After 2016, the leap years up to 2026 are 2020 and 2024.
Riddle 38
What is the largest number of Sundays that a single month can have?
Show answer
5 SundaysA 31 day month is 4 weeks and 3 days. If it starts on a Friday, Saturday or Sunday, it has 5 Sundays, and 6 is impossible.
Riddle 39
Today is Saturday. What day of the week was it 50 days ago?
Show answer
Friday50 days is 7 full weeks plus 1 day, since 50 = 7 x 7 + 1. One day before Saturday is Friday.
Riddle 40
A cheap watch loses 2 minutes every hour. It is set right at 6 am. What time does it show when the real time is 6 pm?
Show answer
5:36 pmFrom 6 am to 6 pm is 12 hours, and 12 x 2 = 24 minutes lost, so the watch shows 6:00 - 0:24 = 5:36 pm.
Hard brain teasers for adults and toppers
Riddle 41
Nine coins look the same, but one is slightly heavier. With a two pan balance, what is the fewest weighings that always finds the heavy coin?
Show answer
2 weighingsPut 3 coins on each pan. The heavier side, or the 3 left off if they balance, holds the coin. Then weigh 1 against 1 from that group.
Riddle 42
How many squares of any size can you find on an 8 by 8 chessboard?
Show answer
204 squaresCount every size: 64 one by one, 49 two by two, and so on down to 1 eight by eight. 64 + 49 + 36 + 25 + 16 + 9 + 4 + 1 = 204.
Riddle 43
At a party, 10 friends each shake hands with every other friend exactly once. How many handshakes take place?
Show answer
45 handshakesEach of the 10 shakes 9 hands, which gives 90, but every handshake is counted twice, so 90 / 2 = 45.
Riddle 44
If you write every number from 1 to 100, how many times do you write the digit 7?
Show answer
20 times7 appears in the units place 10 times (7, 17, ... 97) and in the tens place 10 times (70 to 79), making 20. The number 77 counts twice.
Riddle 45
A train 200 metres long runs at 72 km per hour. How long does it take to cross a bridge 400 metres long completely?
Show answer
30 seconds72 km per hour is 20 metres per second. The train must cover 400 + 200 = 600 metres, and 600 / 20 = 30 seconds.
Riddle 46
One loose sheet of a folded newspaper has page 4 and page 21 printed on it. How many pages does the whole newspaper have?
Show answer
24 pagesPages on the same sheet add up to the total plus 1. So 4 + 21 = 25 means the newspaper has 24 pages.
Riddle 47
A snail at the bottom of a 12 metre well climbs 4 metres each day and slides back 3 metres each night. On which day does it get out?
Show answer
On the 9th dayAfter 8 days and nights it is at 8 metres. On day 9 it climbs 4 more to reach 12 metres and is out before it can slide back.
Riddle 48
What is the smallest number that can be divided exactly by every whole number from 1 to 10?
Show answer
2520This is the lowest common multiple of 1 to 10: 8 x 9 x 5 x 7 = 2520.
Riddle 49
Three different positive whole numbers give the same answer whether you add them or multiply them. What are they?
Show answer
1, 2 and 31 + 2 + 3 = 6 and 1 x 2 x 3 = 6. No other set of positive whole numbers works.
Riddle 50
A shop raises a price by 20 percent and then gives 20 percent off the new price. Compared with the old price, is it cheaper, dearer or the same?
Show answer
Cheaper, by 4 percent1.2 x 0.8 = 0.96, so the final price is 96 percent of the original. The 20 percent off is taken from a bigger number.
Brain teasers: images to share
Save any card and share it. The answer is printed upside down at the bottom of each card.
How to use these riddles
Brain teasers work best when you give yourself a little time. Read the puzzle slowly, underline the numbers and words that matter, and say the question back in your own words before you try an answer. Many teasers hide a trap in one small word such as all but, only or exactly, so check those first.
Teachers can put one teaser on the board at the start of a lesson and give the class two minutes to think. At home or at a party, read a puzzle aloud and let everyone guess before anyone opens the answer. For the harder number puzzles, write down what you know, try small numbers first, and then look for a pattern. If you are stuck, read the working, then try the next teaser of the same type on your own.
Tips
- Read every word of the puzzle twice, because the trick often hides in a small word like but, only or exactly.
- For sequences, write the gap between each pair of numbers and see whether the gaps follow their own pattern.
- Check your answer by putting it back into the puzzle to see that every clue still fits.
More riddles and puzzles
Questions people ask
What is a brain teaser?
A brain teaser is a short puzzle that needs clever thinking rather than school knowledge. Some are number puzzles, some are logic puzzles, and some depend on spotting a trick in the wording.
Are these brain teasers good for kids?
Yes. The quick and logic sections suit children from about class 4 or 5 upward. The hard section is better for older students and adults who enjoy a real challenge.
How can I get better at solving brain teaser puzzles?
Practise a few every day and always read the working after you answer. Over time you start spotting common tricks, such as counting gaps instead of posts or checking every word in the question.
Do brain teasers really help the brain?
Puzzles keep you practising attention, memory and step by step reasoning. They are also a fun way for families and classmates to think together instead of just scrolling.
Where can I use these brain teasers with answers?
Use them as a class warm up, a quiz round at a party, a family game at dinner, or a quick challenge to share with friends on WhatsApp.
Every riddle on this page is written and checked by the Paheli World team. How we make our riddles.