# Tagged Questions

The sum of several numbers divided by their count nicely summarizes the overall size of the numbers involved in a single value.

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### The mean of the of a sum is the sum of the means

Transcription: The mean has good mathematical properties. The mean of a sum is the sum of the means. For example, if $y$ is total income, $u$ is "earned income" (wages and salaries), $v$ is "...
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### problem in understanding overall change in average

The average weight of 5 men is decreased by 3kg when one of them weighing 150kg is replaced by another person. This new person is again replaced by another person whose weight is 30 kg lower than the ...
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### Quantitative Aptitude Average [on hold]

The average weight of a group of boys and girl is $38$ kg. The average weight of boys is $42$ kg and that of girls is $33$ Kg. If the number of boys is 25, then the number of girls is?
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### Does Averaging the score from correlation across multiple variables yield a more accurate correlation score?

This may be a beginner question but I am making a application which I using to do correlation research to be used in financial markets. The application pulls in different data sources and compares ...
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### Find the average value of the function…

Find the average value of the function $$F(x) = \int_x^1 \sin(t^2) \, dt$$ on $[0,1]$. I know the average value of a function $f(x)$ on $[a,b]$ is $f_\text{avg}=\dfrac1{b-a} \int_a^b f(x) \, dx$, ...
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### What are greatest and least average values? [closed]

I'm working on a school assignment in which I've a series and I've to compute these two values, but I can not find the meaning of these terms. I tried searching online resources but wasn't able to ...
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### Removing my averages

thanks for your time and apologies if this is far too simple for this group. I am trying to remove my average from a total average. Meaning: The total average for a subset of data is 55. I am 29% ...
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### Describe the behavior of the average temperature difference of Earth as a function of time. [closed]

So I am having trouble with this question for my ENVS class. I am not sure what type of formula to use or where to start, in no way or form does my professor give an example in our notes. Here is the ...
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### Aproximation for the variance (sum)

Given that we know The mean of a population $\tilde W(t) = \sum_{i=1}^{n}f_{i}(t)*W_{i}$ The variance of the population in the previous step $Var(0) = \sum_{i=1}^{n}f_{i}(0)*(W_{i}-\tilde W(0) )$ ...
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### Average amplitude of the sum of N sines with random phase differences

We have N functions of the form $asin(kx+c)$ Their $a$ and $k$ values are the same their $c$ is a random number between $0$ and $2\pi$ $f(x)$ is the sum all N functions I know $f(x)=Asin(kx+c')$ ...
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### Volume and Average Height

How do you calculate the average number of floors of buildings across a city block when all the buildings are varying heights. Followings in a listing of what the area looks like and the number of ...
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### How can I calculate accuracy of an estimate based on a subset of data?

For example, say I'm trying to determine the average number of steps taken in a day for a population of 100M people. I know the exact number of steps for a random 25M subset of the 100M group (2500 ...
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### How can I get the average angle from a set of three points?

Please forgive me, but I'm not mathematically inclined and i'm trying to solve a problem for a video game i'm developing. My levels are composed of vector shapes and i want to find out what the ...
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### Normalize and Average weighted

Everyday I receive a data of three variables (neutral, negative and positive). ...
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### Boosting v. weighted average

I have been watching an MIT online Artificial Intelligence lecture by Prof. Winston about boosting. The boosting technique uses complicated maths to combine the results from several weak predictors to ...
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### If my average speed is 50 mph, is it better to go 10% faster or 5 mph faster? (These are not the same)

BACKGROUND Suppose we have a journey between $A$ and $B$ where different sections of roads have different speed limits and our average speed is $50$ mph. If when I repeat the journey I travel $10\%$ ...
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### What is the average maximum value of a set of random numbers? [duplicate]

Let $a_1, a_2, a_3, \ldots, a_{10}$ be ten randomly chosen real numbers in the interval [0,1]. Let $m$ be the maximal value out of these 10 numbers. What is the expected value of $m$? (i.e. If i ...
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### Anyone have any good ideas on how to average 2D directions?

Directions, being a cyclical quantity (i.e. if you keep increasing the value, you'll eventually end up back where you started) can't be averaged out like regular numbers. For example, say I have 2 ...
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### The average value of f on region R (double integrals)

If I am given f(x,y) and I calculate the average of the region given by the formula in this image should the average always = (min of f(x,y) +max of f(x,y))/2. I think this is only the case if the ...
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### How can I calculate my current average for my class?

I'm trying to do some what-if scenarios for one of my courses and I'd like someone to double check my work. The grade breakdown is as follows: ...
I have a time series of data points read from an instrument, I also get an estimate of the error ($\sigma$) for each of these readings. e.g. $10.12 \pm 0.05$ $10.09 \pm 0.02$ $10.20 \pm 0.12$ ...