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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.

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arithmetic of the binomial

\documentclass[12pt]{article} \usepackage{amsmath} Bonjour à tous ! Let us have some integers n, k, r satisfiying:: $n/2 \geq \ k \geq 4, r>1$ Let's suppose that there exist an integer a such that: ${n \choose k}=a^r \quad (n \geq 2k)$ From every…
user43414
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Algebraic Expressions

I'm rewriting http://209.141.38.179/mcstatus_v1/ and need an equation. Basically, I have a game server. I know that there are 10 players on that server (Max players being 26). I need to somehow display this number in a progress bar that is out of…
Kondax Design
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Addition composition problem?

I'd like to know how you go about solving the problem below. Does a trick exist other than evaluating substituted values until a solution is found? Furthermore, is there a generic name for such problems? I'll happily change the title of the question…
theconnorpower
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finding percentages between several numbers

My question: if i had an account that yielded $\$60$ in interest annually and another that yielded $\$500$ annually, what percentage better did the second account perform? Is it 830% 60 • X% = 500 X% = 500/60 X% = 8.3 830% 60 • 8.3 = 498
dbp
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Long division differs from calculator

i have been helping my daughter with her long division homework. One of the questions was 172/6 she worked out the answer using the long division tree, and upon checking it found the answer differs when using a calculator. Can anybody answer me…
user125004
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Is there a name for this theorem?

Theorem: If you have a number $x$ with $n$ number of decimal places and another number $y$ with $l$ number of decimal places, then $x \cdot y$ will never have more than $n + l$ decimal places. For example: $63.987 \cdot 56.358 = 3606.179346$ (3…
ryvantage
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Change a digit (unit, tenth or hundred) of a number?

I am trying to find most optimized formula for achieving following result. For example, There is a number 125. I need to change its tenth which is '2' to '7', resulting 175. One formula that I derived: = 125 + {(7 - (125 / 10 % 10)} * 10 = 125 + (7…
Akshat
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two's complement encoding

I'm referring to this article: http://en.wikipedia.org/wiki/Two's_complement I want to convert the following number to two's compliment using 4 bits: Decimal: -6, 6, 1 hexadecimal: C,D,E In the article it says: Algorithmically, to create a two's…
user194076
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A question from Tom Korner's 'The Pleasures of Counting'

Merchant ships sailing independently take 75% of the time to complete voyages compared to ships sailing in a convoy but lose 14% of their number to submarines on each voyage, whilst convoyed ships lose 5% per voyage. We start with a given fleet…
mikoyan
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Averages question

There are five sticks. The average length of any four of them is 600. What is the average of all five? Is it possible to find the average of all with just this information given?
Suy
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How can a negative multiplied by a negative give positive?

On first look this can seem weird. But I can explain what I am looking for. We all know from elementary maths that $(-\times-)=+$. Now, lets say there are 3 cows and I say they will become doubled after one year so $3*2=6$. And lets say I have $-3$…
Brainy
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What's a Multiple?

A quick question-Something that I learned that I forgot throughout the years. If a question asked you for a multiple of 9 and 12, which would be less than 40, would "36" be an answer, as both 9 and 12 can multiply to get 36, yet it fits under the…
JFW
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Addition and subtraction with exponents

I'm doing an Advanced Functions course right now, and I'm wondering about something. Look at this here evaluation/simplification that I did: http://puu.sh/5w3XQ.png What I'm wondering is about the 2^4 - 2^3. I know this is is 2^3 because 2^3 is the…
Threethumb
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Is this a multiplication?

6x-13+4(-3)x=9+2x I'm like, really dumb, I can't tell if if the 4(-3) bit is a multiplication
Delta
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If the mean heart rate of 7 people people is 65 BPM what would an 8th persons heart rate need to be to lower the mean resting heart rate to 63 BPM?

Here it is, I know the answer is 49! (I found it by trial and error!) I just need to know how I can show this in Working! Thanks, Alex
Alex
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