Mathematics Stack Exchange
Mathematics Stack Exchange

Questions tagged [average]

Averages summarise a set of values in one way or another. Without further qualification it most commonly refers to the arithmetic mean, but other averages such as root-mean-square exist.

In its most general definition, an average is a summary of a set of values. Normally it refers to the arithmetic mean, but other means may be employed (geometric, harmonic, etc.) or a transformation may be applied before and after taking a mean (e.g. root-mean-square).

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Is the average of all $x$ such that $0 \le x \le 1$ $ \forall $ $x \in \mathbb{R}$ equal to $\frac{1}{2}$?

Is the average of all $x$ such that $0 \le x \le 1$ $ \forall $ $x \in \mathbb{R}$ equal to $\frac{1}{2}$ ? It may seem this way but how can we show that indeed it is $\frac{1}{2}$. We know that the number of elements in $0$ to $1$ of real numbers…
Keneth Adrian
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What is the best way to average the frequency of Chinese characters in a sentence?

I'm trying to find the best way to assign a "frequency score" to sentences in Chinese. Basically, I have a database which tells me how frequent each Chinese character is. From that, I would like to evaluate how "easy" a sentence is compared to other…
laurent
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Math Average Basics, Error % calculation, and Blood Pressure.

I saw on the Olympics once when they were doing scoring for team events, that on some events the judges would take each members performance, eliminate the highest and lowest members performances, and average the remaining performances to give an…
Francis Rodgers
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Estimated wait time for a library book

A library has 20 copies of a book that circulates for 3 weeks. All copies are out and there 40 people on reserve ahead of me. How do I estimate the wait time?
jeff
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Sum and sum of average not matching

I'm struggling with the following problem. I have a table showing the % of a population that like (say) bananas in three locations, the population of each location, and the total population who like bananas in each location (the previous two…
Jon
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Approximate simple moving average knowing only previous SMA?

I know it's possible to calculate a regular average incrementally knowing the previous average, the next number and the number of items. But is this possible for a moving average of N items, at least approximately? To calculate the exact SMA in…
pati
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Calculating average value of points over a period of time

I have several values plotted over a period of time on a line graph. The length of time between values is not uniform (i.e. one value could be 3 days after the one before, which itself could be 2 weeks after that one). Visualised as a line graph,…
johneth
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Does missing a number from a set affect the average?

Firstly, apologies for an uninteresting title, and whether this is absolutely newbie maths. I'm a programmer, and when it comes to maths and me - the wheel is going, but the hamster is dead. On To the question. We use a third-party review site for…
Moo-Juice
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New Average with a number deleted

A set of consecutive integers were written down: $1, 2, 3, 4, 5, ... x-1, x, x+1, ... n-2, n-1, n$ One number, $x$, is deleted. The arithmetic mean of the remaining numbers is $602/17$. What does "$x$" and "$n$" equal? I managed to get two equations…
user113864
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Vote "0-10" dignity.

I have this problem very difficult for me to solve. I have a company and some employees. Each of them expresses an opinion on some apples of varying quality. The vote can be: 0 1 2 3 4 5 6 7 8 9 10 For example, the first two apples are rated in…
ginolin
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Weighted Average Over Time for Data Projection (aka Weighted Moving Average) - Mathematically Correct Way to Determine Weights?

Consider the following data set: Say graduation rates for a specific college's undergraduate program that are the following: Year # of Graduates Year 11 10,500 Year 12 10,750 Year 13 11,000 Year 14 11,750 Year 15 9,000 Year…
SEStudent
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Help with formula to calculate "earnings"?

I'm looking to calculate earnings on a writing platform, based on a variety of metrics. Unfortunately I suck at math, and am unable to come up with the exact, proper formula to find an average. Hopefully someone can help me understand how to…
FMB
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Calculate how many occurrences are needed to achieve average

I have the following numbers from a ticketing system: Closed Tickets: 10 Transferred Tickets: 10 Total Tickets: 20 The current average is: Closed tickets/Total tickets = 10/20 = 0.5 = 50% What I need to calculate is how many additional Closed…
Serge Inácio
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Adding averages

I am working with data on the feeding behavior of beef cattle. The data provides from the electronic trough system are the total daily time spent in the trough (in seconds), time spent in the daily trough with food consumption (in seconds), time…
Valente_95
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How to get a weighted average with different sample sizes

I have some data on a cyclists distance traveled and hours it took. I want to get a weighted average of MPH, where more recent samples have a higher weight. The weights in the table use an exponential time decay to get the appropriate weight 0.99 ^…
radio23
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