Mathematics Stack Exchange
Mathematics Stack Exchange

Questions tagged [recreational-mathematics]

Mathematics done just for fun, often disjoint from typical school mathematics curriculum. Also see the [puzzle] and [contest-math] tags.

Recreational mathematics is a general term for mathematical problems studied for the sake of pure intellectual curiosity, or just for the enjoyment of thinking about mathematics, without necessarily having any practical application or expectation of deep theoretical results.

Recreational mathematics problems are often easy to understand even for people without an extensive mathematical education, even if the theory they lead to may turn out to be surprisingly deep. Thus, recreational mathematics can serve to attract the curiosity of non-mathematicians and to inspire them to develop their mathematical skills further.

Many typical recreational mathematics problems fall into the fields of discrete mathematics (combinatorics, elementary number theory, etc.), probability theory and geometry. Important contributors to recreational mathematics are Sam Loyd and Martin Gardner.

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counting up to 100

I have one question if someone could help me how to calculate it: If I have some amount of money (Euros). What the amount I have if I need to have the amount once doubled plus a half of the amount plus a quarter of the amount plus 1 to have 100…
pul5
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Customer Lifespan Value calculation with few data

I have a mathematics problem that I am unable to solve. If anyone could help, that would be much appreciated. A company runs an online business and needs to know its average customer lifespan value. To do that, they only have the following data…
kfug
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If $(a_1 b_1 + a_2 b_2 + a_3 b_3)\lt0$ and $(a_1 c_1 + a_2 c_2 + a_3 c_3)\lt0$; what's about $(b_1 c_1 + b_2 c_2 + b_3 c_3)$?

I found that problem: Let's suppose $(a_1 b_1 + a_2 b_2 + a_3 b_3)\lt0$ and $(a_1 c_1 + a_2 c_2 + a_3 c_3)\lt0$; what's about $(b_1 c_1 + b_2 c_2 + b_3 c_3)$? I have no other infos about that problem because I found it on a sticky notes in an old…
DOmonoXYLEDyL
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TI 84 CAN'T SOLVE THIS SIMPLE PROBLEM

why does my TI 84 answer .06 divided by 365 = 1.643835616E -4?? the answer is .000164383
Brian Proskin
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2 answers

Add the following numbers and find the answer?

Sum the $3$ numbers from the list $?+?+?=30$ Fill the boxes using $1,3,5,7,9,11,13,15$ You can also repeat the numbers
Hamza.S
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Is there a name for this occurrence when dividing cost by unit.

So, to understand how I noticed this let me explain a few things. I work for a tire and auto repair shop where one of my jobs main tasks is to put inventory we receive from warehouses into our computer system. This requires me to put the inventoried…
Lord Shadowheim
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How t0 find numbers divisible by 3 between 200 and 400 without testing every number in the range?

How to find numbers divisible by 3 between 200 and 400 without testing every number in the range? And explain the solution to a 10 year old!
user3919652
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Recreational mathematics - Digit sum

Find the sum of all 3-digit positive numbers N that satisfy the condition that the digit sum of N is 3 times the digit sum of N+3 Can you help me with this question?
chndn
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4 answers

Strange math question; Find $2 \mathbin\triangle 4 =\text{?}$

$\newcommand{\d}{\mathbin{\triangle}}$How do you solve this question; $$1 \mathrel\triangle 0 = 3$$ $$1 \d 2 = 12$$ $$0 \d 2 = 5$$ $$1 \d 5 = 2 \d 3 = 96$$ Find $$2 \d 4 = \text{?}$$ Here it is the answer to the equation(please keep in mind that i…
Kitiara
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Rental Problem between tenants

Okay, first of all, I'm writing this while I am battling a major cold so please don't laugh if the Answer jumps out at you. Let's call this the rental problem. Both Mark and Pat rent a place together, they each submit $\$775.00$ for the damage…
x937q
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Given $ x^m=y^m ; so \; x=y \;or\; -y$ when m is even. Now $ 2^0 = 3^0 \; but \; 2 \neq 3 $ . How to reason mathematically

The question may sound silly but is there a simple logic to counter the paradox.I will be glad to know if there is. Thank You. Edit: x,y $\in R\;\; x,y \neq 0$, m is a integer. Now x = y when m is odd x = y or -y when m is even. and x and y cant be…
Rohith Penumala
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How many minimum weights do you need to measure all weights from $1$kg to $1000$kg

You can place weights on both side of weighing balance and you need to measure all weights between $1$ and $1000$. For example if you have weights $1$ and $3$, now you can measure $1,3$ and $4$ like earlier case, and also you can measure $2$, by…
alia
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Give the answer of following question

Puzzle ⚪ +⚪ +⚪ __________ =⚪⚪⚪ Each symbol represents a digit, and identical symbols represent identical digits. Can you tell the digits represented by blue, red and white circles?
user207008
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partnership problems

A,B and C started a business by investing Rs 7,000, Rs 5,000 and Rs 3,000 respectively. If they earned a profit of Rs 9,000 , find the share of A ? Note: Rs = Indian Rupees
Amna Fayyaz
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Equation that outputs digit in 1's 10's 100's slot

I need an equation that outputs the digit in the slot of my choosing EX1: I want the 10's slot in 1837 EX2: I want the 10's slot in 123456789 EX3: I want the 1000's slot in 93037352 I also need it to be super simple, preferably only using +,-,/,x
CocoaMix86
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