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7 Puzzles That Will Test Your Mental Skills

MindYourDecisions

731,606 views

How many can you solve? Skills tested: outside the box thinking, creativity, logic, pattern recognition, Harvard entrance exam style question, interview question, mathematics, puzzle solving, problem solving, genius test

all 7 = genius
4 to 6 = great
0 to 3 = subscribe and try again ;)

0:00 how many ducks?
1:25 bicycle tricycle
3:36 logic boxes
6:16 fish sticks
7:34 change dots
10:11 tablets A and B
14:12 area circle

puzzle 1 how many ducks
https://www.rd.com/article/how-many-d...
puzzle 2 how many tricycles
https://math.stackexchange.com/questi...
puzzle 3
Facebook: 1060322677328094
https://mathematicaldonuts.substack.c...
https://www.indy100.com/viral/brain-t...
https://www.thesun.co.uk/living/20989...

puzzle 5
https://www.reddit.com/r/theydidthema...

puzzle 6
https://www.mathsisfun.com/puzzles/ta...
Reddit: goldman_sachs_supposedly_asked_this_riddle_during

puzzle 7
Problem
Reddit: find_the_area_of_the_circle
solution by u/testtest26
Reddit: mehv44p
hard to prove straight line
Reddit: geometry_question

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20 Comments

@talkingscribe8898 1 year ago

If you have two different medications that look exactly the same, either your doctor is giving you placebos or you need to get a new pharmacist.

@NicD 1 year ago

The pill puzzle has such refreshingly-low stakes: "you'll get sick and ruin the end of your vacation", rather than dying, being trapped forever, becoming destitute, etc.

@JoeBorrello 1 year ago

For the duck puzzle, I need to point out that double billing is illegal.

@tjpprojects7192 11 months ago

Thumbnail:
1. Put all 4 pills in a line.
2. Split all pills in half.
3. Eat all halves of pills on ONE side of the halves.

Depite not knowing the order, and because the 4 pills are 2 A's and 2 B's you know that each half will be exactly 1/2 of the 2 A's and 2 B's, which will thus be a full dose of 1 A and 1 B.

@OimYoutoube 1 year ago

These are not small ducks at all. These are ducks of perfectly acceptable size. Some would say that these are HUGE ducks, i'll have you know.

@bartmeijer1954 1 year ago

6:01 : "because the box is in car 2" Interesting!

@KirniAUT 1 year ago

Puzzle 7: i tested this in my CAD software and it seems that no matter which size both squares have, if 2 corners of each square touch the circle point F is in line with A and D. thats really interesting and I need to dig into this why this is ;-)

@qovro 1 year ago

It's a good thing that real medicines have unique imprints.

@OrbitTheSun 1 year ago (edited)

6:00 "The box is in car 2."

@TonboIV 1 year ago (edited)

Puzzle 5: (1.0 + 1) * (1.0 - 1) = |0|, and indeed 2*0 is equal to the absolute value of 0. This solution is slightly less trollish than the "correct" one.

@Ryan50Ryan 1 year ago

14:15 "Hey guys, this looks like a fun one." -Andy Math.

@KarolKuczmarski 1 year ago

Any answer to problem 1 is correct, as long as it's how many ducks you actually *saw*.

@Ringcaat 1 year ago (edited)

Oh my gosh, question 7 was way too hard and complicated compared to the rest! But anyway, you can use the Intersecting Chords Theorem to establish that if AD extends to point F and ED extends to point B (which they both will if angle CDG is 45 degrees), then the math works out and you get 4*2rt(2) = 2*4rt(2). This doesn't quite prove that the squares form exactly a 45 degree angle, but it does prove that that's one possible angle they can form. So if the question always has the same answer, you can make that assumption. I did that and got the right answer for the area. Intuitively, it also seems as though there is no freedom in terms of how large the angle can be.

@Dexaan 1 year ago

Pill puzzle: grind them into a powder and dissolve them in water. Drink half of the water on the first day and half on the second.

@reachthroughreality 1 year ago (edited)

puzzle 6: clean, crush, mix, divide, snor---use. Baffled some of the brightest minds, but none of the grimiest.

@verkuilb 1 year ago

That last question deserved a video to itself!!

@joseignacioparamio8453 1 year ago

10:00 For puzzle 5 you can do it with just one dot. (10+1)*(1.0-1)=|0|

@Phraxas52 1 year ago

Puzzle 1: Does the word "Duck" count? Just because I see a bill, can I assume with certainty it's a duck? Just because I see two bills and two sets of feet, can I assume that is only 2 ducks and not 3 with the one with the bill hiding its feet and the one with the feet hiding its bill? Can I assume all ducks with multiple heads showing are separate ducks instead of mutants with multiple heads? There's a lot of rules missing here, but yeah 16 does sound reasonable.

@koenth2359 1 year ago

Bicycle/tricycle problem: if all used a bicycle we'd have 32 wheels. Since there are 6 more wheels than that, 6 students must have a tricycle instead.

@KlokJammer 1 year ago

Puzzle 3: Boxes 1 and 3 contradict each other, which means they cannot have the same truth value (i.e. one is true and one is false). Since only one box can be true, and it has to be either 1 or 3, therefore 2 is always false. 2 says the car is not in this box, and 2 is false, therefore the car is in 2. There's no need to do what ifs.