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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Earth and Sun - fast question

Guys is my logic correct? If Earth travels around the Sun in $29.78$ km/s and I have to calculate how long will it take to travel $1$km I did following: $1s / 29.78 = 0.03358$ (to $5$ d.p) I think it's ok but I would like to get confirmation on…
There is nothing we can do
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Solving a (tricky) arithmetic congruence equation in the general case

Out of sheer curiosity, I am looking for the solutions of the congruence equation : $n^{n+km} \equiv n$ mod m for every k natural integer where $k,n,m \in N$ where m=$p_1^{\alpha_1}p_2^{\alpha_2} . . .p_n^{\alpha_n}$, the $p_i$ are (distinct) primes…
Evariste
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Dust coating a length of road that is 1.25 miles long.

A length of road is 1.25 miles. 8 landowners along the road would like to split the cost of dust coating the road. The cost of dust coating is at $53 per 100 feet. The county will reimburse the landowners 55% of the total cost. How much will each…
user238971
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Why do we invert then multiply when dividing fractions?

I have looked up various sites online. They only explain it in a very basic arithmetic way. Would someone explain to me why is $\displaystyle\frac{x}{\frac{1}{2}}$ is $\displaystyle\frac{2x}{1}$?
wa7d
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Profit and Loss : Manufacturer

A manufacturer undertakes to supply 2000 pieces of a particular component at Rs.25 per piece. According to its estimates, even if 5% fail to pass the quality tests, then he will make a profit of 25%. However, as it turned out, 50% of the…
Vibhu
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modular problem in arithmetic

hello can someone please help me to solve this problem: 2008 mod 71, 9 square mod 41, 34 suare mod 71 b)determine all a and b that verify a square mod 41=40 b square mod 71=20 this is my answer: a) 2008 mod 41=40 2008 mod 71=20 9…
user172892
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How do I compute $-6(-4)^{n-1} + 8(-4)^{n-2}$?

How do I compute $-6(-4)^{n-1}$ + $8(-4)^{n-2}$ ? I recall that as long as the number from both operands (in this case: -4) are the same, I can actually "add" them together. But the problem is the -6 from the first operand and the +8 from the second…
Nicholas
  • 559
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Progessive terms adding and minusing

What is the value of $$1+2+3-4+5+6+7-8+9+10+11+12...+97+98+99-100 \ ?$$ Any help is appreciated, thank you! I added the terms as an AP then subtracted 10 then all the numbers that were missed out, not sure if this is right though.
Daniel
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Is it possible to convert fraction to decimal using only addition and subtraction?

I am working on a programming challenge that requires me to implement addition, division, and modulo using only addition and subtraction. Cool, simple enough: function multiply(x, y) { var result = 0; for (var i = 0; i < x;i++) { result =…
chopper draw lion4
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Calculate ideal value from graph

I have a question to ask, but before I do, let me just tell you that this might be a trivial - or even downright silly question. I only have a basic understanding of math, so please do try to keep that in mind when answering. Thank you so much. So,…
Zuiq Pazu
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Evaluating $6^2\div 2(3)+4$: is the answer $10$ or $58$?

Evaluating $$6^2\div 2(3)+4$$ I understand how people are getting $10$ but I am getting $58$ because I am not distributing the $2$ to the $3$ inside the parentheses. Is that correct?
Django
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base arithmetic conversation decimal to (+3)

I've asked the question because I've never seen a base like that before. For example, $76_{10}$ = $(?)_{+3}$ . The issue is that what does $_{+3}$ stand for ?
NewCoder
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How to calculate so that when width increases, height will decrease

As stated in title. Width is dynamic, hence the calculation :p The tricky part is that width can not be on the right side of the divide sign (\), as defined by the css calc() syntax. I haven't thought about how I want the height to decrease. But…
BigName
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How to count the number of integers with a fixed leading digit which are less than a given number?

Consider the numbers $1$ to $5000$. Numbers starting from the digit $2$ would be $2$, $20-29$, $200-299$, $2000-2999$; total would be $1111$. How can one derive a formula for the same? The first input would be a number, and the second input would…
user12334
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How to find a relation between given numbers to get a given result?

I have f(2, 3, 6) = 5/6; f(4, 3, 12) = 17/6; f(3, 3, 9) = 11/6; f(2, 0, 2) = 2; How can I find the relation f for the given values?
Mirceac21
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