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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2
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2answers
37 views

Is there a name for the way I am averaging the cost of cards?

My buddy and I were discussing different ways of deciding how much mana to include when constructing a deck. Without thinking much about it I used a method of finding the average converted mana cost ...
1
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1answer
37 views

Weighted average of multiple weighted factors

Lets say a factory machine runs as follows: Day 1: $3$ widgets per minute $\times 1000$ minutes $\times 1$ kg per widget $= 3000$ kg. Day 2: $5$ widgets per minute $\times 800$ minutes $\times 1.5$ ...
1
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2answers
23 views

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 ...
0
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0answers
20 views

What is the appropriate way to average a set of slopes?

I have a set of line slopes (output from linear regressions) and I'd like to combine them to yield some measure of the 'slope' of the set. However, simply taking the mean of the numbers doesn't make ...
2
votes
2answers
109 views

How do I find the average of top list items? [closed]

Here's the situation: I have a lot of "top lists" like so: list1: iPhone 6 Galaxy S5 LG G4 list2: Galaxy S5 OnePlus One iPhone 6 LG G4 Nexus 5 list3: LG G4 Galaxy S5 Nexus 5 And so on... ...
0
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0answers
9 views

Another name for mode frequency

Is there another term for the number of times the mode number occurs in a list/array of numbers or 'the frequency of the mode' in a list/array of numbers? Apologies if this has been asked before - I ...
1
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1answer
24 views

Looking for an equation that reflects the majority of a collection

I'm working on a computer program, part of which involves sifting through large collections of numbers (by large, I mean 16 million+ numbers). I expect these collections to almost entirely be composed ...
1
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1answer
20 views

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 ...
3
votes
3answers
54 views

Why this statistical equation is true?

Pardon my ignorance. I also don't know how to properly show the equation. So I attached URL of latex... Why this equation is true for any real number $k$, when $\overline{X}$ is average of individual ...
0
votes
1answer
38 views

Integrated average value of a multivariate function doesn't match average obtained through simulation.

So, recently I have been trying to calculate the expected area of a convex cyclic quadrilateral with perimeter $1$. Nonetheless, I will only post what's relevant to the issue - the fact that the ...
0
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2answers
64 views

The average age of 30 boys in a class is 16, including the teacher it is 17. What is the teacher's age?

The average age of $30$ boys in a class is $16$. If the teachers is included the average increases by $1$. What is the teacher's age? Options: $37$ yrs $30$ yrs $47$ yrs $57$ yrs None of these ...
0
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0answers
11 views

Weighted Average Using Rankings

So I have this data and I've ranked each category for each person. The best being 1. I can average them , just add up and divide, but I need to weigh them. If I weigh them like normal: ...
1
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0answers
29 views

Expected waiting time - simplified

I need some assistance with a calculation I'm trying to do. I have access to surgery waiting times data (date arrived, date completed) and I want to figure out the expected waiting time for a new ...
0
votes
2answers
24 views

Mean value of positive numbers in an arbitrary set of numbers

I have a set with an arbitrary amount of positive and negative numbers. Now I want to calculate the mean value of all numbers inside the set which are greater than $0$. Is there a mathematical way of ...
0
votes
4answers
27 views

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 ...
0
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2answers
25 views

General forumla for taking running average of a running average?

Let's say I have an array of $N$ numbers: $n_1, n_2, .... n_N$ I then calculate a running average of those numbers, by averaging $A$ numbers at a time, which will result in the following array: $...
0
votes
1answer
30 views

Calculate new average from two other averages with its respective totals/counts

I have the next film named Blade Runner and it has two version (director cut and theatrical cut) and I rate the director cut with a 7 and the theatrical cut with a 8, so the average would be: (7 + 8) ...
0
votes
1answer
38 views

Midpoint between two real numbers

Well, it's quite clear that if I try to count mean average of any two numbers, I always get the midpoint. Is it really the whole intuition behind this concept? Or is there something hidden behind this ...
0
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1answer
32 views

Calculate average lifespan

We want to calculate the average lifetime of our customers. For each customer we know when they joined, whether they are still with us and if not, what date they left us. Our company has exponential ...
0
votes
1answer
16 views

Mixture & Alligation problem

In what ratio must a person mix three kinds of wheat costing him 1.20,1.44 and 1.74 dollars per kg., so that the mixture formed is worth 1.41 dollars per kg? a)11:77:7 b)12:7:7 c)ratio other than a ...
3
votes
4answers
121 views

Determine drug concentration over time, given its halflife and dosage

I want to calculate which of two doses is going to have the most active ingredient over the total time of an experiment. So as an example let's say I have a drug which has a halflife of 5 hours, and ...
0
votes
0answers
20 views

Determine contribution percentage

I'm trying to determine the individual category percentages once their weights have been applied. The easiest way to describe what I'm asking is to show my workings: ...
1
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0answers
38 views

Median of medians vs. single median

I have 10 sets. Each set corresponds to a user. Each set contains a different amount of floating point numbers. Each such number corresponds to a response time (of a user). Now I would like to ...
1
vote
1answer
24 views

Calculate average time of person in system when ins and outs are roughly equal

I have a system that has people going through a sensor for in, a sensor for out. I'm measuring ins and outs through the day, ...
1
vote
1answer
63 views

How can I curve a test grade knowing only the average and the highest score?

I am trying to get a raw score for my test grade, but I don't know anything about the distribution of test grades; all the information I have is the average and the highest score (and of course my own ...
1
vote
0answers
14 views

Do I need to calculate the weighted average in these cases?

I'm aware of the concept of calculating a weighted average but the data I'm working with is confusing me. I couldn't find any similar examples when I did a search. Here's an example. We have a number ...
0
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2answers
62 views

A can do a job in three hours, B can do it in 4. Hjow long does it take them together?

As it says in the question: if one person can do a job in 4 hours, and another can do the job in 3 hours, how quickly can they do the job together in they can work together? My attempt was this: ...
0
votes
0answers
11 views

Does (messing up) FIFO affect average cycle time?

I'm currently in the midst of a corporate class on process improvement and ran into the following situation: Workflow process containing several steps. No step is skipped or done out of order. ...
1
vote
1answer
54 views

Attaining the expected value over iterations

Is my implementation of the expected value correct? I conclude that the average number of iteration of this algorithm will be 1/3, but seems completely wrong. Rand() outputs either 0 or 1 (uniform) ...
-2
votes
1answer
64 views

Simultaneous Equations. [closed]

Erin goes off on a long bike ride at 10km/h. One hour later her brother starts chasing after her at 16km/h. How long will it take Alistair to catch up to Erin? Solve with simultaneous equations.
4
votes
2answers
44 views

Maximise difference between mean and median

I have a set of numbers and I want to maximise the difference between the mean and the median by removing a given number of elements. For instance I have the following set: ...
1
vote
2answers
35 views

Average $y$ from a range of $x$ in a parabola

Given a parabolic/quadratic formula such as $ax^2 + bx + c =y$, how do I get the average value of $y$ given a range of $x$ ($x_{min}$ to $x_{max}$). Real world example: if my formula represents the ...
3
votes
2answers
63 views

How do I properly average these percentages?

I have attendance records for an annual event: person 1: $4$ of $8$ attended $= 50.00$%, or every $2$ years person 2: $1$ of $4$ attended $= 25.00$%, or every $4$ years ...
1
vote
2answers
111 views

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 ...
0
votes
0answers
27 views

Average number of $5$-card draws before all $52$ cards in a deck are drawn.

So an interesting question was brought to me today and I'm not sure how to formulate the equation to answer it. A person draws $5$ cards from a deck, writes the cards down, puts the cards back in the ...
1
vote
0answers
19 views

Approximate values from point groupings

Say I am given a set of values: \begin{bmatrix}0.9&1.1&1&1.95&2&2.05&2.95&2.95&3.1&3\end{bmatrix} Is there a way I can get the 'center' or 'average' values 1, 2, ...
0
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0answers
10 views

Multiple server queuing model

I have come across the following problem in one of my courses: Let's suppose a patient in a hospital is waiting to be picked by one of the two doctors available. The time till a new pacient arrives ...
1
vote
2answers
18 views

Using double integration to compute an average yields a different result than computing it without integration

I'm self-learning multivariable calculus and am using double integration to compute the average value of $f(x,y)$ over some region. I'm trying to solve the following simple problem using two different ...
0
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1answer
15 views

Generalizing exponential moving average to n samples

Assume that we have a moving average like this: $E_t = a*S_{t-1}+(1-a)*E_{t-1}$ where $E$ would be an estimate we are interested in, and $S$ is a sample we take at each point in time. Now, if we ...
1
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0answers
29 views

Averaging speeds

I read the answer to this question: http://stackoverflow.com/questions/34794664/how-should-i-calculate-the-average-speed-by-road-segment-for-multiple-segments/34795821#34795821 Can anyone please ...
0
votes
2answers
38 views

Find the percent of boys and girls

I have a basic school academic question which despite of trying very hard I was unable to find a solution - Average score of girls is an exam is $67$ and that of boys is $62$. Find the percentage of ...
1
vote
3answers
48 views

Number of Likes and Dislikes to Star Rating system

I have a 5 star rating system that outputs a recommendation. A user inputs a rating based on a Like or Dislike. What I would like to know is how to convert the number of likes and dislikes into a ...
0
votes
0answers
32 views

Weighted average of unit vectors

I am trying to determine the yaw (z) axis of a vehicle given a bunch of sensors, each of them subject to different kinds of error. This means I get a bunch of unit vectors for the z axis, expressed ...
0
votes
1answer
53 views

Calculating a weighted average for different pay rates and different hours.

I'm trying to take the money earned over several days - each with unique hours worked and dollars earned per hour (hrs and $/hr). What I've done is multiply each days' # of hours by its rate to get ...
-1
votes
1answer
36 views

Average velocity question? [duplicate]

I usually know how to do these but this one gives me trouble. If a ball is thrown into the air with a velocity of 46 ft/s, its height in feet t seconds later is given by $y = 46t − 16t_{2}$. (a) ...
0
votes
1answer
27 views

If I subtract a number (from a sequence) from the average of all the numbers in that sequence - what do I have?

If I have a number (from a sequence) and I then subtract that number from the average of that sequence- what do I have? I would describe it as a 'deviation from the average' - but is there a better ...
0
votes
1answer
12 views

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, ...
1
vote
1answer
28 views

Average case of element comparisons when searching for an element x with a specific probability

I just had a midterm, and unfortunately our professor has stated that he will neither discuss nor post any solutions to the midterm, so I'm posting a question that was on it here in hopes that someone ...
0
votes
1answer
72 views

How can I average two integers digit by digit?

I would like to take two integers of similar size (about the same number of digits) and average them, without having to first add them, and then divide the result by two. Let's say I have the ...
0
votes
0answers
33 views

How to find the best-case and average-case number of comparisons performed by a comparison tree?

So I'm reviewing some material before a midterm tomorrow and I came across this question: ...