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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Help with creating a formula to calculate grade needed on test to pass?

This is probably a simple math question and yet I'm struggling to understand it, any help would be extremely appreciated. Say if I have 2 test results, 50% on Test 1, test worth is 10% of final grade 50% on Test 2, test worth is 30% of final…
nnnm
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How to solve averages without using formula

For the question, "The average of $30$ numbers is $40$ and that of other $40$ numbers is $30$. Find average of all numbers.", the options given are: $35$ $34$ $34\frac{1}{2}$ $34\frac{2}{7}$ I solved it like,…
aarbee
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Power of a square wave signal

I have a signal with half-amplitude $A$ and period $T$ and I want to calculate the average power of the signal. I think I remember the power of a signal $x(t)$ to be $$\frac{1}{T}\int_{0}^{T}|x(t)|^2dt$$ but how do I apply this to a square wave?
dingari
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Calculating weighted score of test

I have a test containing questions with 3 levels of difficulty: +------------+------------+-------+ | Question | Difficulty | Score | +------------+------------+-------+ | Question 1 | 1 | 100% | +------------+------------+-------+ |…
Germstorm
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Calculating average over a year

I'm trying to calculate the average count of employees for a group of companies. I need to exclude months where a a company had no employees. Please verify that my approach is correct. January February March April May June July August …
Antarr Byrd
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Economics Marginal Cost and Average Cost

I am in Computer Engineering but this year the university gave me choice for two electives with one being Psychology and the other Economics...So this being my first economics course I am really stumped! It doesn't really make much sense to me so I…
user2997307
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average and total average

why is it when I get the average of the column "per hour", it's different from the total?
Wil
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Effect of removal of numbers while calculating average

My question is , lets say we have the numbers 1,2,3,.....,n numbers . 2 consecutive numbers are removed. The avg of the numbers after the removal of numbers be m let the numbers removed be k,k+1 can we come up with a formula that relates m,n,k
Bhargav
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Mean values using eigenvalues - how?

I thought the definition of the average value of $f(x)$ was $f* = \frac{1}{T}\int_0^T f(t)dt$ How do I get from this definition to the definition of the mean value of a function in terms of eigenvalues? The mean value of a function is the sum of all…
bobby
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Which average to use with range

Say I wanted to calculate how much rain in terms of volume falls on the Earth each day or hour, etc. In order to do so I'd first need to know how much water is in a single raindrop. I know that and it ranges from $10^{-6}$ to $10^{-3}$ cubic inches…
Milo
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A Basic Math Question on Averages

Okay this is going to sound really stupid but I'll ask anyway... I need to get a $5.5$ accumulative GPA (the highest is a $7.0$). For the last $16$ classes I've done my GPA is sitting at $5.44$. I'm taking $3$ classes this semester, what would I…
user141562
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Running a Cumulative Average

I'd like to run a cumulative average and I'm wondering if my process is sound. Here's a small dataset: Row 1: $\frac{2\cdot 60}{58} = 2.07$ Row 2: $\frac{4\cdot 45}{44} = 4.09$, $\frac{2.07+4.04}{2} = 3.07$ Row 3: $\frac{3\cdot 60}{60} = 3.00$…
TechFanDan
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Taking the time average of the product of two waves

How might one go about calculating the time average of the product of two identical waves with different phases? For example, what would be the time average of: $$ \cos(k x-w t) \cdot \cos(kx-wt+a) $$ and how would you get it? Thanks!
Mason
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What kind of a mean value is this?

I wasn't that sure what kind of mean value the following is, I hope you can help me out: What it's about: I have this testseries of about 30 elements, that delay the boot sequence of an embedded System. I checked them separately to say, element #3…
user3085931
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Five members of a wrestling team are weighed and ...

An average weight is calculated after each player is weighed. Of the average weight increases by 2 pounds after each player is weighed, how much is the last player than the first? My answer is 8 pounds. I first mark the five members with letters a…
Valkyrie
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