0
votes
1answer
34 views

Average percentage formula

I have something like: Price Quantity Tax (%) 2.2 34 8 1.3 29 7 And so on... After that I get something like: ...
0
votes
2answers
28 views

What formula would you use to cast an average of several numbers into a smaller range?

Say I have four numbers ranging in value from 15-95. If I want to, for a simple example, say that if the average of the four numbers is 15 (lowest possible value), that would relate to 2 on a scale of ...
3
votes
1answer
20 views

Simplified Averages - Always true?

While working on an "average rating" function for a website, I came across an idea for simplified averages, but I want to confirm that it always works. If it does, I might be able to keep a running ...
0
votes
0answers
17 views

is f-mean a general form for all well-behaved means?

Can one claim that all well-behaved means can be written in form of f-mean? I mean means like logarithmic, etc. wikipedia link
0
votes
2answers
53 views

Bringing numbers in a set closer together

I'm trying to express the relative scale of items compared to an "average" scale for all items in the set. This produces values like { 0.5, 1.8, 0.3, 1.2 ... } I then wish to use this number to ...
0
votes
2answers
90 views

Calculate the average sales per day in 2010.

In 2005, Company K was 730 000 units of the car market. Total sales is 50% of the total cars sold in 2010. Calculate the average sales per day in 2010. Calculation: 1) 50/100 x 730 000 2) 730 000 x ...
5
votes
1answer
87 views

continuously averaging a stream of numbers

Ok, so I'd like a little help with the mathematical theory behind something I'm doing in a program. I've got a stream of numeric inputs, and I need to find the average of all the numbers in this ...
2
votes
3answers
62 views

What is the mean score for the $20$ rolls?

A fair die is rolled twenty times. The results are shown in the bar graph. What is the mean score for the $20$ rolls?
1
vote
2answers
51 views

Problem Solving using Algebra

If Peter is $7$ years older than Sharon and John is twice as old as Peter, work out how old Peter is if the average of their ages is $19$. Thanks! :)
2
votes
3answers
332 views

Averaging the values of $\cos x$ over one period

I'm calculating the average value of $\cos x$ by dividing the period $[0,2\pi]$ into ten intervals which means that I should be looking for the average of 11 results. What I get is approx. 0.09. The ...
1
vote
1answer
164 views

Minimum Numbers to find the given average.

Average score of the player (sum of scores in all the games / no. of games) is given. How Can we find the minimum number of games the player should have played to achieve that average. scores are non ...
0
votes
2answers
137 views

How can i solve this problem about averages?

The average (arithmetic mean) bowling score of $n$ bowlers is $160$. The average of these $n$ scores together with a score of $170$ is $161$. What is the number of bowlers, $n$? I tried this: $$X'*n ...
0
votes
1answer
40 views

Formula for normalising with respect to average

I have a 5*5 grid (as in the figure). At each point there are 5 dishes of varying numbers of bacteria. I'd like to write a formula which calculates the average of these 5 and then divides by the ...
0
votes
1answer
143 views

Algorithm to Get a Product score based on rating

I am trying to device a algo for product score. Here are the inputs User rates a product on 5 different criteria out of 10 Each criteria has a different weightage with all adding up to 100% There ...
1
vote
2answers
53 views

Constructing an average equation - Standardized Test

A question in the standardized test is: The average of $n$ numbers is $a$. If $x$ is subtracted from each number the average will be a) $(ax)/n\quad$ b) $(an)/x\quad$ c) $an-x\quad$ d) ...
0
votes
1answer
40 views

Which of the following cannot possibly be the average - Standardized Test

I came across a question while preparing for a standardized test that is kind of confusing. Hope you guys could help me out here. The question is: Three men have weights that range from 110 to 135 ...
0
votes
1answer
174 views

Calculating average of word problem

I was preparing for a standardized test and came across the following problem: During a closeout sale 30 suits are sold at \$60 each.The price is the reduced to \$50 each and 20 suits are sold. At ...
0
votes
2answers
75 views

How to get the average of $a$, $b$ when all you know is the average of $a,b,c$ and the value of $c$?

I need to figure out some averages for some javascript I'm writing. The data I have is: I know the average of $a$, $b$ and $c$. I know the value of $c$. I do not know the values of $a$ and $b$. ...
2
votes
2answers
526 views

How do I average out to a particular number if I have to add another number to get that average?

So, lets say, that you have the following numbers (4, 15, 3, 22) and you have to add the fifth number (which I would call X) and they must average out to say 20. What do you have to do? I figured ...
2
votes
1answer
387 views

Need help with a math trick question

I wasnt sure where to ask this but since this is an algorithmic question here it goes. I've come face to face with a math problem and can't seem to get over it for the last couple of days. It goes ...