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Questions tagged [arithmetic]

Questions on basic arithmetic involving numerical quantities only. Questions involving variable values (other than the result of the operation) should be placed under the (algebra-precalculus) tag. Questions about number theory (sometimes called "arithmetic") should not use this tag and should instead use (number-theory) or (elementary-number-theory).

Arithmetic is defined as operations upon numbers using $4$ main operations along with many others:

addition - the sum of two numbers

subtraction - the difference of two numbers also defined as the addition of negative numbers

multiplication - the area of a rectangle with sides of lengths equal to the two operands

division - the number of times one number can be subtracted from another before equaling zero. Sometimes it will allow decimals and in other cases there will be a remainder left over when a number doesn't go into another evenly

See Arithmetic.

6283 questions
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How to form a 'master rank' from a list of other ranked items?

This is my first question across the StackExchange network, and it seems a lot easier than other questions I've seen on here (so I hope it doesn't bore you!), but I can't seem to come up with the answer myself. I'm re-writing an old browser game.…
NathanR
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logic Accounting trick

Tom went to shop with a fake \$1000 for shopping.He bought items worth \$800 from shopkeeper A A.The shopkeeper had no change so he went to borrow from shopkeeper B. He came back and gave Tom his change.Shopkeeper B realized that shopkeeper A had…
Willie
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Is $4 \times 6$ defined as $4 + 4 + 4 + 4 + 4 + 4$ or $6 + 6 + 6 + 6$?

There are long debates among Indonesian netizens about this http://www.globalindonesianvoices.com/15785/is-4x6-the-same-as-6x4-this-primary-school-math-made-controversy-in-social-media/
u100899
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What do I do after this?

The question goes.. In a recent marathon, $\frac{1}{10}$ of the participants finished in less than $3$ hours. $\frac{1}{3}$ of the remaining participants finished in $4$ hours or less. Out of those who took more than $4$ hours, twice as many…
Ardine
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Convert 1-5 Grading Scale to 1-100 Grading System

I am creating a formula in Excel to convert 1-5 Grading Scale to 1-100 Grading System Suppose that I have the following table: 97-100 = 1.00 94 - 96 = 1.25 91-93 = 1.50 88-90 = 1.75 85-87 = 2.00 82-84 = 2.25 79-81 = 2.50 76-78 = 2.75 75 =…
Jayson Tamayo
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How and why can it be true that some decimals that sometimes go on forever in base 10 such as $1\over 3$ change to good numbers in base 12?

I've noticed on a math channel on YouTube that some of these decimals from fractions in the decimal system such as $1\over 3$, which equals $0.\overline3$, which goes on forever, doesn't show off this thing in the dozenal, or duodecimal, system:…
ReliableMathBoy
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get 100 with the help of five 2

how to get 100 with the help of +, -, /, * and five 2s? 22222 = 100 I should put arithmetic operants between two s and get 100. PLease help
Jahongir Rahmonov
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Using a decimal addition table for subtracting

I'm reviewing the math I missed in school and I've come across a decimal addition table in a book along with a description of how to use the same table for subtracting. I'm having trouble parsing the description on how to subtract, though. "The…
tcv
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Check if $(a_n)$ is arithmetic progression with a given $S_n$

We have $(a_n)$ with $S_n = n^2$. Check if $(a_n)$ is an arithmetic progression or not. NOTATION $$(a_n)_{n\ge1}\\S_n = a_1 + a_2 + \cdots + a_n, \forall n\in \mathbb{N}^*$$
Victor
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Let $a = −215$ and $b = 17$. Find the integers $q$ and $r$ with $0 \leq r < b$ such that $a = qb+r$.

Let $a = −215$ and $b = 17$. Find the integers $q$ and $r$ with $0 \leq r < b$ such that $a = qb+r$. I don't know where to stop $$a = qb + r$$ $$-215 = q \cdot (-17) + r$$ help me continue. thanks
user3924310
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If 8 divides $a^2$ + $3b^2$, prove that both a and b are even.

Question: Prove that if $a$ and $b$ are integers and 8 divides $a^2$ + $3b^2$, then both a and b are even. I'm able to prove that 8 divides $a^2$ + $3b^2$ if both $a$ and $b$ are even using the fundamental theorem of arithmetic and expressing 8 as…
user197996
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What will be the remainder?

I'm stuck with this problem I'm trying to solve from about an hour. Here's the question. What is the remainder when (3^202)+137 is divided by 101? There are 4 options -> 36, 45, 56, 11 I want to know the answer of the question with proper and…
Electrifyings
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Does Conversion rates affect the profit earned?

About $~\$100~$ were given to me as an initial investment. I converted them to INR and traded with it in buying stocks and also selling stocks. I am now left with say $~$*Rs.*$6000~$ today. As all of you are aware that USD prices varies from day to…
Rpj
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Approximate to whole number without calculator

Approximate this number to the nearest whole number without a calculator: $2^{\sqrt{5}}$ I don't know how to do this problem. Can you help me? My answer key says $5$. Also, how do I approximate $2^\pi$ and $3^e$? The answers are $9$ and $20$,…
Sofia
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Even powers and perfect squares

Does $2^{2k}$ (where $k$ is a natural number) always result in perfect squares?If so, why?I just tried it with a few values and it appears to be true. I need the result for this to simplify a question.
Paradox 101
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