What number of are you able to resolve?
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 procuring 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 difficult!
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 mean of 8 mph whereas the boy walks at a mean of 4 mph. The canine runs at a continuing 10 mph backwards and forwards 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 under. Resolve for the lacking weights m, n, w.
Puzzle 7
This comes from a Math Kangaroo competitors.
One of many figures under 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 positive 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 publicizes, “Now I do know the favourite determine too!”
Which is Frank’s favourite determine?
As regular, 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 maintain studying.
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“All might be nicely when you use your thoughts on your choices, and thoughts solely your choices.” Since 2007, I’ve devoted my life to sharing the enjoyment of recreation concept and arithmetic. MindYourDecisions now has over 1,000 free articles with no adverts because of group assist! Assist out and get early entry to posts with a pledge on Patreon.
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Reply To 7 Baffling Puzzles
(Just about all posts are transcribed shortly after I make the movies for them–please let me know if there are any typos/errors and I’ll appropriate them, thanks).
What number of are you able to resolve?
0:00 Puzzle 1
Dividing into 2 and three equal shapes is simple. Dividing into 4 is sort of difficult. So that you could be primed that dividing into 5 shapes might be even more durable. However in no way! All it is advisable do is divide into 5 equal rectangles with straight traces!
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 entails a center coin together with a nook left coin. There are 12 options by these strategies.
6:40 Puzzle 3
In a procuring 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 cut 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 may also resolve 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 info we now 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 difficult!
The meant answer is -3 + 5 = 2.
An outdoor the field answer 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 mean of 8 mph whereas the boy walks at a mean of 4 mph. The canine runs at a continuing 10 mph backwards and forwards 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 difficult. However you don’t must do any type of tough 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 under. 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 precise weights to get 3.
Now think about 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 under 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 positive 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 publicizes, “Now I do know the favourite determine too!”
Which is Frank’s favourite determine?
answer
Categorize the figures by the data every is instructed.
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 positive Shilpa doesn’t know. If Shilpa had heard hexagon, she would know the determine is the inexperienced hexagon. Colin can solely ensure 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 instructed circle, she would nonetheless not ensure if the determine is blue or yellow. Since she is bound, she should not have heard circle. Colin additionally deduces this, so he eliminates circle from his prospects as nicely.
Colin
yellow: star, sq.
blue: triangle
Colin states he does know the favourite determine now. Had he been instructed yellow, he would nonetheless be uncertain. So he will need to have been instructed blue.
Subsequently 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/ebook/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
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