Mathematics Stack Exchange
Mathematics Stack Exchange

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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Is there any law or axiom for the position and quantity of a natural number?

I am interested in this question. We all know that for example the natural number seven consists of seven 1 (7=1+1+1+1+1+1+1) and it is located between 6 and 8. But is there any law or axiom that would confirm this, or all people just agreed among…
Honza Prochazka
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How is the following arithmetic sequence solved?

Apologies to bother you with this, but how is the following arithmetic sequence solved? $$\dfrac1n \left(\sum_{k=1}^{n-1}\dfrac{n-k+1}2\right)$$
user74185
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Converting solution of linear equations to slope intercept form

I will use a very simple linear equation to make my point: $$3x = 2$$ $x$ will always be equal to $2/3$. This equation in itself has no use in graphing. So if we want to be able to apply that equation in graphing, is it legal to convert that to…
JohnMerlino
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Obtaining the total from a percentage

$x$ is $20$ percent of $t$. t=?; //to compute x=198; Example compressed = 64; uncompressed = (100 / 20) * 64; //is it correct? How can I compute $t$?
kannanrbk
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Is the following statement true? Why?

$\frac{a}{b}\neq0 \Rightarrow (a\neq0\land b \neq0)$ At first sight that seems quite obviously true, however, wouldn't $b = 0$ also fit the condition? $\frac{a}{0}\neq0$
0x6C38
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Show that $e^{\frac{3\ln(2+\sqrt3)\ln(2-\sqrt3)}{ 2\ln(2-\sqrt3)-\ln(2+\sqrt3)}}= 2 + \sqrt{3}$

How from $e^{\frac{3\ln(2+\sqrt3)\ln(2-\sqrt3)}{ 2\ln(2-\sqrt3)-\ln(2+\sqrt3)}}$ do I get $2+\sqrt{3}$? This is a simple problem that I am unable to solve. I tried using properties of logarithms, but I cannot find $2+\sqrt{3}$, as Wolfram says...…
user561334
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Why ZZ = (10×Z)+Z when Z = 4

I started to learn mathematical fundamentals course at brilliant.org and there is a puzzle Maybe is too late or I just don't get it, why is ZZ = (10×Z)+Z and how they get this equation from the question ? Because the formula does not even fit,…
Muflix
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Converting marks to % when the lowest possible mark is not zero

A multiple choice questionnaire has $10$ questions. The marking scheme is $+5$ for correct answer, $−1$ for wrong answer.... The best mark would be $50$ and the worst mark $-10$. How can I convert the mark to percentage?
dietmar
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BODMAS Rule for simple calculations

I was helping my little sister solve a sixth grade math problem which went something like this - Z = 4 + 3 - 3 + 2 What is the final value of Z ? In this case , my brain directly jumped to the BODMAS and I did the addition part first. I thus got -…
Aurav S Tomar
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Properties of Operations problem

Please help I can't figure out this problem Let Z denote the set of integers: { …, -3, -2, -1, 0, 1, 2, 3, …}. Define an operation  on Z by x  y = 2(x + y). a. Is Z closed under  ? Explain. b. Is  associative? Explain. c. Is there…
Moises Flores
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Are these expressions equal?

I'm reading a physics booklet on radioactivity and at one part during the calculations it says: $$A(0) = 6.0 \cdot 10^{23} \times \frac {\ln 2}{(8 \times 24 \times 3600)} = N(21) = 6.0 \cdot 10^{23} \cdot {\left(\dfrac{1}{2}\right)}^{21/8}$$ But…
YakDanaGulDuDana
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Find all positive integers $n $ such that $n^2+n+7$ devided by 13. An idea please

Find all positive integers $n $ such that $n^2+n+7$ devided by 13. An idea please
Wer Wer
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calculate multiplication factor to go from 1 to 100 in y attempts

I have totalnumberofdays and percentage on day 1. I have to incrementally grow the currentpercentage every day so that it reaches 100 percent on day n For ex: If totalnumberofdays = 7, percentage on day 1 = 1 currentpercentage would be equal to…
systemdebt
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wrong arithmetic concerning addition and percentages

The problem: A realtor takes a sale commission of 6%. A buyer offered 412,250 to buy a house and the realtor said he's willing to accept only 4% commission. The realtor says the 2% he gave up is worth 8245$, and if this amount is added to 412,250…
user122415
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I'm attempting a breakdown of a certificate of analysis

THCa=3.43% CBDa=14.77% CBD =0.31% CBGa=0.50% Total CBD=CBDa*0.877+CBD;LOQ Using the equation provided by the lab I have been unable to reach the same answer of 13.26% total CBD %. I am assuming the semicolon is simply stating that the CBD% only…
anthony klingler
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