Easy math puzzles
Poll
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| | 4 votes (7.54%) | ||
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| | 4 votes (7.54%) | ||
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| | 5 votes (9.43%) | ||
| | 12 votes (22.64%) | ||
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53 members have voted
June 15th, 2026 at 4:45:07 PM
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Original solution still valid, but here’s a more efficient way to get 14.
((10 + 5 + 7*3)^.5 + 5*2)^.5 + 5*2=14
Multiplication is shown for simplicity but can be accomplished using addition only. Highest number displayed is 36
The last math puzzle (beer jugs) also used fives and sevens as the only valid inputs. Coincidence??
((10 + 5 + 7*3)^.5 + 5*2)^.5 + 5*2=14
Multiplication is shown for simplicity but can be accomplished using addition only. Highest number displayed is 36
The last math puzzle (beer jugs) also used fives and sevens as the only valid inputs. Coincidence??
It’s all about making that GTA
June 15th, 2026 at 5:38:30 PM
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What, nobody's going to try the negative root?
√ 5+5+5+5+5= -5
+7= 2
+7+7= 16
√ 16 =-4
+7+7= 10
+5+5+5= 25
√25= -5
+5+7+7= 14
√ 5+5+5+5+5= -5
+7= 2
+7+7= 16
√ 16 =-4
+7+7= 10
+5+5+5= 25
√25= -5
+5+7+7= 14
June 15th, 2026 at 6:29:22 PM
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The problem says you’re using a calculator. Show me a calculator that gives a negative value for a square root.
Also, how does √ 5+5+5+5+5= -5 ?
Also, how does √ 5+5+5+5+5= -5 ?
It’s all about making that GTA
June 15th, 2026 at 7:16:24 PM
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Quote: Ace2The problem says you’re using a calculator. Show me a calculator that gives a negative value for a square root.
Also, how does √ 5+5+5+5+5= -5 ?
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The ASCII radical sign available here, that's just how it looks, no way to extend it over the whole statement. I suppose I should have used parentheses.
And I'll show you a calculator that gives a negative square root when you show me one that can only add 5 and add 7 and take square roots! This is a very unusual calculator to begin with, and unless stipulated we can make no assumptions about which square root.
June 15th, 2026 at 11:01:08 PM
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All submitted answers look correct. Well done group!
I got this one from one of my puzzle videos from the Ted-Ed YouTube channel. This one is titled, "Can you solve the giant cat army riddle? - Dan Finkel"
Direct: https://youtu.be/YeMVoJKn1Tg?si=RCtKeyqbfmB5oj0J
I got this one from one of my puzzle videos from the Ted-Ed YouTube channel. This one is titled, "Can you solve the giant cat army riddle? - Dan Finkel"
Direct: https://youtu.be/YeMVoJKn1Tg?si=RCtKeyqbfmB5oj0J
"My life is spent in one long effort to escape from the commonplace of existence. These little problems help me to do so." -- Sherlock Holmes
June 24th, 2026 at 2:41:15 PM
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This is more of a math question than a math puzzle.
In the game of craps, many casinos charge a 5% commission (of the bet amount) on a win only when buying the 4/10.
My understanding is that a $40 lay bet on 4/10 would win $59 for $40 at a casino that collects the commission on win only. But this doesn’t seem right since a lay bettor would be paying twice the $vig as a buy bettor in the long run.
If laying the 4/10, shouldn't the casino charge the 5% (of potential win amount) on a LOSS only? For example, if laying the 4 for $40 to win $20, you'd actually lay $41 to win $61 for $41.
This would ensure the casino makes the same $ vig on a player laying the 4 for $41 as a player buying it for $20. In a casino that charges the vig up front, they make the same $vig on a $20 buy and a $40 lay, so that seems to be the intent.
In the game of craps, many casinos charge a 5% commission (of the bet amount) on a win only when buying the 4/10.
My understanding is that a $40 lay bet on 4/10 would win $59 for $40 at a casino that collects the commission on win only. But this doesn’t seem right since a lay bettor would be paying twice the $vig as a buy bettor in the long run.
If laying the 4/10, shouldn't the casino charge the 5% (of potential win amount) on a LOSS only? For example, if laying the 4 for $40 to win $20, you'd actually lay $41 to win $61 for $41.
This would ensure the casino makes the same $ vig on a player laying the 4 for $41 as a player buying it for $20. In a casino that charges the vig up front, they make the same $vig on a $20 buy and a $40 lay, so that seems to be the intent.
Last edited by: Ace2 on Jun 24, 2026
It’s all about making that GTA
June 25th, 2026 at 6:32:49 AM
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Quote: Ace2This is more of a math question than a math puzzle.
In the game of craps, many casinos charge a 5% commission (of the bet amount) on a win only when buying the 4/10.
My understanding is that a $40 lay bet on 4/10 would win $59 for $40 at a casino that collects the commission on win only. But this doesn’t seem right since a lay bettor would be paying twice the $vig as a buy bettor in the long run.
If laying the 4/10, shouldn't the casino charge the 5% (of potential win amount) on a LOSS only? For example, if laying the 4 for $40 to win $20, you'd actually lay $41 to win $61 for $41.
This would ensure the casino makes the same $ vig on a player laying the 4 for $41 as a player buying it for $20. In a casino that charges the vig up front, they make the same $vig on a $20 buy and a $40 lay, so that seems to be the intent.
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If you are betting 41 against the casino's 20, that's a commission of 2.5% (1/40) on the entire bet, win or lose.
June 25th, 2026 at 1:06:52 PM
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That's incorrect. A 2.5% commission of the lay amount (paid on win or loss) would pay $60 for $41 on a win since the $1 commission is never returned. Essentially you’re wagering $41 vs $19. That's a house edge of 1 - 2/3 * 60/41 =2.44%. It doesn't work out to exactly 2.5% since the $1 commission is added to the bet instead of subtracted from it.Quote: ThatDonGuy
If you are betting 41 against the casino's 20, that's a commission of 2.5% (1/40) on the entire bet, win or lose.
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However, when the 2.5% commission is paid on loss only, a win pays $61 for $41 for a house edge of 0.81%
The casino calls these a 5% commission on the potential win amount instead of 2.5% on the lay amount
I suppose not too many people have analyzed this since lay bettors are rare and the commission on win only for the buy bet is relatively new
Last edited by: Ace2 on Jun 25, 2026
It’s all about making that GTA
June 26th, 2026 at 7:22:40 PM
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On a 4x4 grid of dots, how can you go through all 16 dots with 6 lines without removing your pen from the paper?
"My life is spent in one long effort to escape from the commonplace of existence. These little problems help me to do so." -- Sherlock Holmes
June 26th, 2026 at 7:47:33 PM
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Quote: WizardOn a 4x4 grid of dots, how can you go through all 16 dots with 6 lines without removing your pen from the paper?
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June 26th, 2026 at 9:52:11 PM
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Quote: ThatDonGuy
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I agree!
"My life is spent in one long effort to escape from the commonplace of existence. These little problems help me to do so." -- Sherlock Holmes
July 3rd, 2026 at 8:26:31 AM
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Alex, Bob, Charlie and Dylan (represented by lower-case letters) must each get to his respective home (represented by upper-case letters) through a snow-covered field. They may not leave the field and may not cross paths. How can they do it?
Note: image updated.
Last edited by: Wizard on Jul 3, 2026
"My life is spent in one long effort to escape from the commonplace of existence. These little problems help me to do so." -- Sherlock Holmes
July 3rd, 2026 at 12:52:44 PM
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My answer:
Dog Hand
Dog Hand
July 3rd, 2026 at 1:18:38 PM
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July 3rd, 2026 at 1:26:11 PM
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Quote: DogHandMy answer:
Dog Hand
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You're right for the question as stated. However, in seeing your solution I realize I made it too easy. You shouldn't be allowed to go behind the kids. Here is my revised image.
"My life is spent in one long effort to escape from the commonplace of existence. These little problems help me to do so." -- Sherlock Holmes
