What number of are you able to remedy?
Puzzle 1
That is stated to be an interview query at Google. A sq. is split into 4 quadrants and has an L-shaped space eliminated, as proven. Divide the higher left white space into 2 equal shapes, the decrease left white space into 3 equal shapes, the decrease proper white space into 4 equal shapes, and the higher proper into 5 equal shapes.
Puzzle 2
Puzzle 3
In a buying market, 10 carts are pushed collectively and measure 4 m from finish to finish. In one other association, 7 carts are pushed collectively and measure 3 m from finish to finish. What’s the size of a single cart?
This puzzle comes from Mathematical Explorations for Younger Minds by Bálint Hujter, Dániel Lenger, Gábor Szűcs.
Puzzle 4
They are saying that is just for IQ above 200; it’s tough!
Puzzle 5
This puzzle comes from the sport present The 1% Membership.
A brother and sister take their canine for a stroll. The sister jogs at a median of 8 mph whereas the boy walks at a median of 4 mph. The canine runs at a continuing 10 mph forwards and backwards between them and he doesn’t cease at any level. After an hour how far will the canine have run?
Puzzle 6
Weights are suspended and balanced beneath. Resolve for the lacking weights m, n, w.
Puzzle 7
This comes from a Math Kangaroo competitors.
One of many figures beneath is Frank’s favourite determine.
Colin and Shilpa need to work out which is the favourite. Frank tells Colin the colour of his favourite determine (Shilpa is conscious that Colin is aware of the colour). Frank tells Shilpa solely the form of his favourite determine (Colin is conscious Shilpa is aware of the form). The next dialog occurs.
Colin says, “I have no idea Frank’s favourite. However I’m certain that Shilpa doesn’t know the determine both.”
Shilpa says, “At first I didn’t know, however now I do know Frank’s favourite determine.”
Colin declares, “Now I do know the favourite determine too!”
Which is Frank’s favourite determine?
As common, watch the video for an answer.
0:00 Puzzle 1
2:55 Puzzle 2
6:40 Puzzle 3
10:35 Puzzle 4
12:43 Puzzle 5
14:19 Puzzle 6
16:44 Puzzle 7
Or hold studying.
.
.
“All shall be nicely in the event you use your thoughts on your selections, and thoughts solely your selections.” Since 2007, I’ve devoted my life to sharing the enjoyment of sport concept and arithmetic. MindYourDecisions now has over 1,000 free articles with no advertisements due to group assist! Assist out and get early entry to posts with a pledge on Patreon.
.
.
.
.
.
.
M
I
N
D
.
Y
O
U
R
.
D
E
C
I
S
I
O
N
S
.
P
U
Z
Z
L
E
.
.
.
.
Reply To 7 Baffling Puzzles
(Just about all posts are transcribed rapidly after I make the movies for them–please let me know if there are any typos/errors and I’ll right them, thanks).
What number of are you able to remedy?
0:00 Puzzle 1
Dividing into 2 and three equal shapes is simple. Dividing into 4 is kind of tough. So that you is perhaps primed that dividing into 5 shapes shall be even tougher. However in no way! All it is advisable do is divide into 5 equal rectangles with straight strains!
2:55 Puzzle 2
Rows 2 and three have 3 cash every, so it is advisable take away or add a coin to every of these rows. Contemplating the 4 center cash, you possibly can transfer a pair of diagonal cash to the highest or backside. One other set of options includes a center coin together with a nook left coin. There are 12 options by these strategies.
6:40 Puzzle 3
In a buying market, 10 carts are pushed collectively and measure 4 m from finish to finish. In one other association, 7 carts are pushed collectively and measure 3 m from finish to finish. What’s the size of a single cart?
Puzzle comes from Mathematical Explorations for Younger Minds.
Visually eradicating 3 carts will scale back the size by 1 m. So simply take away 3 carts two occasions, and you find yourself with 1 cart that measures 1 m. Easy!
You too can remedy the issue algebraically. Let x be the size of 1 cart, and let d be the extra distance by pushing a cart on the finish. From the given data now we have:
x + 9d = 4
x + 6d = 3
Subtract the second from the primary to get:
3d = 1
d = 1/3
Then substitute for d into the second equation to get:
x + 6(1/3) = 3
x + 2 = 3
x = 1
The size of a cart is 1 m.
10:35 Puzzle 4
They are saying that is just for IQ above 200; it’s tough!
The meant resolution is -3 + 5 = 2.
An out of doors the field resolution is 9 + 5 = E, the place E represents 14 in hexadecimal.
12:43 Puzzle 5
This puzzle comes from the sport present The 1% Membership.
A brother and sister take their canine for a stroll. The sister jogs at a median of 8 mph whereas the boy walks at a median of 4 mph. The canine runs at a continuing 10 mph forwards and backwards between them and he doesn’t cease at any level. After an hour how far will the canine have run?
The canine zigzags an infinite variety of occasions, so the query appears fairly tough. However you don’t must do any form of troublesome calculation!
The canine runs at a continuing 10 mph for a time of 1 hour, so the canine should run a distance of 10(1) = 10 miles. That’s it!
14:19 Puzzle 6
Weights are suspended and balanced beneath. Resolve for the lacking weights.
2(1) = m(1)
m = 2
2(1) = n(2)
n = 1
Add the left weights to get 4. Add the suitable weights to get 3.
Now contemplate the highest bar.
4(3) = w(1) + 3(3)
12 = w + 9
w = 3
16:44 Puzzle 7
This comes from a Math Kangaroo competitors.
One of many figures beneath is Frank’s favourite determine.
Colin and Shilpa need to work out which is the favourite. Frank tells Colin the colour of his favourite determine (Shilpa is conscious that Colin is aware of the colour). Frank tells Shilpa solely the form of his favourite determine (Colin is conscious Shilpa is aware of the form). The next dialog occurs.
Colin says, “I have no idea Frank’s favourite. However I’m certain that Shilpa doesn’t know the determine both.”
Shilpa says, “At first I didn’t know, however now I do know Frank’s favourite determine.”
Colin declares, “Now I do know the favourite determine too!”
Which is Frank’s favourite determine?
resolution
Categorize the figures by the knowledge every is informed.
Colin
inexperienced: star, triangle, sq., hexagon
yellow: star, sq., circle
blue: triangle, circle
Shilpa
star: inexperienced, yellow
triangle: inexperienced, blue
sq.: inexperienced, yellow
hexagon: inexperienced
circle: blue, yellow
Colin states he doesn’t know the determine, however he’s certain Shilpa doesn’t know. If Shilpa had heard hexagon, she would know the determine is the inexperienced hexagon. Colin can solely make sure of Shilpa’s uncertainty if he didn’t hear inexperienced.
Shilpa explains she didn’t know at first, confirming that she didn’t hear hexagon. Upon listening to Colin converse, she will be able to deduce Colin didn’t hear inexperienced. So she is left with the next choices:
Shilpa
star: yellow
triangle: blue
sq.: yellow
circle: blue, yellow
If Shilpa had been informed circle, she would nonetheless not make sure if the determine is blue or yellow. Since she is certain, she should not have heard circle. Colin additionally deduces this, so he eliminates circle from his potentialities as nicely.
Colin
yellow: star, sq.
blue: triangle
Colin states he does know the favourite determine now. Had he been informed yellow, he would nonetheless be uncertain. So he will need to have been informed blue.
Due to this fact Frank’s favourite determine is a blue triangle.
References
0:00 Puzzle 1
https://www.youtube.com/watch?v=CEUFZvxd01M
https://medium.com/puzzle-sphere/famous-interview-puzzle-to-divide-squares-google-amazon-microsoft-observation-pattern-skills-26e48b9e2d4e
2:55 Puzzle 2
https://puzzleaday.wordpress.com/2025/02/25/the-deceptive-ten-tokens-puzzle/
https://www.pleacher.com/mp/puzzles/miscpuz2/mobcoin.html
6:40 Puzzle 3
Mathematical Explorations for Younger Minds
https://hyperlink.springer.com/e book/10.1007/978-3-031-64185-5
10:35 Puzzle 4
https://puzzling.stackexchange.com/questions/98027/unexpectedly-difficult-matchstick-problem
12:43 Puzzle 5
https://only-connect-questions.fandom.com/wiki/1percent25_Club_Season_2_Episode_7
https://www.reddit.com/r/theydidthemath/feedback/1gz55z1/request_how_far_would_the_dog_be_from_the/
14:19 Puzzle 6
https://www.reddit.com/r/SmartPuzzles/feedback/1i5ailj/how_heavy_is_the_turquoise_weight/
16:44 Puzzle 7
https://www.reddit.com/r/askmath/feedback/11mz42r/any_help_tia/
https://www.reddit.com/r/askmath/feedback/1j22b13/im_stumped_this_question_makes_no_sense_to_me/
https://www.mathkangaroo.in/media/pdf/1296718881_6_Student-G-11_Test_Paper.pdf
Coin
https://commons.wikimedia.org/wiki/File:1884_trade_dollar_rev.jpg
MY BOOKS
If you are going to buy via these hyperlinks, I could also be compensated for purchases made on Amazon. As an Amazon Affiliate I earn from qualifying purchases. This doesn’t have an effect on the worth you pay.
E book scores are from January 2025.
(US and worldwide hyperlinks)
https://mindyourdecisions.com/weblog/my-books
Thoughts Your Choices is a compilation of 5 books:
(1) The Pleasure of Sport Principle: An Introduction to Strategic Considering
(2) 40 Paradoxes in Logic, Likelihood, and Sport Principle
(3) The Irrationality Phantasm: How To Make Sensible Choices And Overcome Bias
(4) The Greatest Psychological Math Methods
(5) Multiply Numbers By Drawing Traces
The Pleasure of Sport Principle exhibits how you need to use math to out-think your competitors. (rated 4.2/5 stars on 564 evaluations)
40 Paradoxes in Logic, Likelihood, and Sport Principle incorporates thought-provoking and counter-intuitive outcomes. (rated 4.2/5 stars on 81 evaluations)
The Irrationality Phantasm: How To Make Sensible Choices And Overcome Bias is a handbook that explains the various methods we’re biased about decision-making and presents methods to make sensible selections. (rated 4.2/5 stars on 55 evaluations)
The Greatest Psychological Math Methods teaches how one can appear like a math genius by fixing issues in your head (rated 4.3/5 stars on 148 evaluations)
Multiply Numbers By Drawing Traces This e book is a reference information for my video that has over 1 million views on a geometrical methodology to multiply numbers. (rated 4.5/5 stars on 57 evaluations)
Thoughts Your Puzzles is a group of the three “Math Puzzles” books, volumes 1, 2, and three. The puzzles matters embrace the mathematical topics together with geometry, likelihood, logic, and sport concept.
Math Puzzles Quantity 1 options basic mind teasers and riddles with full options for issues in counting, geometry, likelihood, and sport concept. Quantity 1 is rated 4.4/5 stars on 138 evaluations.
Math Puzzles Quantity 2 is a sequel e book with extra nice issues. (rated 4.2/5 stars on 45 evaluations)
Math Puzzles Quantity 3 is the third within the collection. (rated 4.3/5 stars on 38 evaluations)
KINDLE UNLIMITED
Lecturers and college students world wide typically electronic mail me in regards to the books. Since schooling can have such a big impact, I attempt to make the ebooks accessible as extensively as doable at as low a worth as doable.
At present you possibly can learn most of my ebooks via Amazon’s “Kindle Limitless” program. Included within the subscription you’re going to get entry to hundreds of thousands of ebooks. You do not want a Kindle system: you possibly can set up the Kindle app on any smartphone/pill/laptop/and so forth. I’ve compiled hyperlinks to applications in some nations beneath. Please verify your native Amazon web site for availability and program phrases.
US, record of my books (US)
UK, record of my books (UK)
Canada, e book outcomes (CA)
Germany, record of my books (DE)
France, record of my books (FR)
India, record of my books (IN)
Australia, e book outcomes (AU)
Italy, record of my books (IT)
Spain, record of my books (ES)
Japan, record of my books (JP)
Brazil, e book outcomes (BR)
Mexico, e book outcomes (MX)
MERCHANDISE
Seize a mug, tshirt, and extra on the official web site for merchandise: Thoughts Your Choices at Teespring.
