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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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How do I compute a double weighted average? In other words, an average with two weighting factors.

This might be a simple question... I was wondering, how does one take a double weighted average? (honestly, don't know if that is what it is called). For example, let's say that we are working with data from the table below: Cellphone type | # of…
Frankie
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Explain weighted moving average in a way for a beginner programmer to implement it in Google Spreadsheets

I needed to implement a moving average that can handle missing data. The catch is that the number of data points to be considered should be a variable easy for me to adjust. See…
Kim Stacks
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Compute average distance between numbers $0$ to $10$

I'd like to calculate the average difference between two numbers, each between $0$ and $10$. I calculated this for integers and came up with an average distance of $4$. My method: there are $10$ ways to obtain a difference of $1$, $9$ ways to…
zazizoma
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Difference between averaging and taking n-th root of products

It seems like taking the n-th root of the product of n values is analogous to the traditional form of averaging. For example: $$ \frac{5+5+5}{3} = 5 = \sqrt[\leftroot{0}\uproot{0}3]{(5*5*5)} $$ But they do not always produce the same…
jds
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Get from array n % entries closest to the average.

There is an array of numbers: 1,5,5,10,5,8,3,4. Is there a formula to get the n % of it closest to the average? For this example average is ~5, and if I want 50% to be counted, numbers 3,4,5 should stay and numbers 1, 8, 10 should be dropped. Is…
wasd
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Calculate average speed over x-distance

This is probably a very easy calculation to do, but I cant seem to solve it/confirm its 100% correct. Lets say we have the following data to calculate the average speed with: - distance from A to B = 1243 meters - default speed to move an object…
Richard Avalos
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Maximum Profit at which combination

A dealer deals only in colour TVs and VCRs . He wants to spend up to Rs.12 lakhs to buy 100 pieces. He can purchase colour TV at Rs. 10,000 and a VCR at Rs. 15,000. He can sell a colour TV at Rs. 12,000 and a VCR at Rs. 17,500. His objective is to…
Arpit Bajpai
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Reporting numbers that vary

I'm timing how long various parts of a computer program takes to run, with the intent of including this in a research paper. There are fluctuations in the timing based on the usual things inside a computer (other processes running, scheduling, timer…
Alan Wolfe
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Averaging several factor of multiplication function

So, I have these kind of equations: $k_{A_1}*k_{B_1}*k_{C_1} = f_1$ $k_{A_2}*k_{B_2}*k_{C_2} = f_2$ ... $k_{A_7}*k_{B_7}*k_{C_7} = f_7$ What I have is $f_1$,$f_2$,...$f_7$ Is there any way to get the average value of $k_A$,$k_B$, and $k_C$?
Bharata
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How do you calculate a rolling average speed?

I am making a speedometer for my bike with an arduino and I have got it to display speed now I want to display average speed. But I'm struggling to think of how to do it. The speed is checked 1000 times a second. If anyone could help that would be…
mapexmbirch
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Calculating the average speed of a trip when given 3 different speeds for 3 percentages of distances.

The question: In a trip, $10$% of the way, Lucy drives uphill at an average speed of $56$mph; $10$% of the distance is downhill where she can manage an average speed of $72$mph. On flat ground, Lucy can has a average speed of $63$mph. What is Lucy's…
Shreyas Kannan
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Weighted Averages from the world of GMAT..

I am really confused about how this question has been solved. I've given the question, author's approach and then mine. Can you help me figure out why/ why not I have gone wrong? Thanks in advance, Suraj Question A milkman has 20 L of milk. He…
surajvissa
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Calculating Weighted Averages – selecting a correct numerical scale for several variables

I have the following variables that i am going to use to calculate a weighted average: Variable Format Weight applied (out of 1) A Percentage 0.2 B Percentage 0.1 C Percentage 0.1 D …
bob56
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Averages of Power Sets

I've been studying power sets and thought this was interesting. $\frac{x+y+\frac{x+y}{2}}{3} = \frac{x+y}{2}$ This is if we have a set of 2 elements, x and y, and we get it's powerset, find the averages of each subset then the average of those…
user268346
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Intuition: Average vs. Average Rate of Change

I intuitively understand the examples below, but I don't see an "average" in the average rate of change (I see a ratio of two delta values). What is the relationship between the average (arithmetic mean) and the average rate of change? 2+3+4 / 3 = 3…
mellow-yellow
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