Finding 'x' in Excel - excel

I have a problem I need help with, please.
I want to find x in the following manner:
((a+x)/(b+x))>=c
This would be an extension to a simple calculation in my workplace, d=a/b where:
b is the total number of incoming calls we receive
a is the number of calls we could handle out of b, the total
d shows our performance
So far so good. No function needed.
But we also have a target, c, in percentage - let's say 60% or 0.6
Ideally a/b should be bigger than c.
IF it is not, I'd like to know how many more incoming calls we need that are also handled (with x added to both a and b above) therefore slowly raising our performance over time.
x would show this extra number of handled calls, say, "5"
I do not know what type of mathematics it is (I cannot recall it, shame on me)
I do not know how to achieve it in Excel
Can someone please help? thank you!

((a+x)/(b+x))>=c
then
a+x >= c(b+x)
then
a+x >= cb+cx
then
a-cb >= cx-x
then
a-cb >= (c-1)x
then
(a-cb)/(c-1) >= x
So if you have values for a,b,c then the range for x is defined.

When you cannot solve the equation "analytically", you might use the "goal seek".
Use a param in any range, such as "A1". Fill it with any value looking like your answer (if you want a percentage put 50%, etc.).
A1=3
B1=((a+A1)/(b+A1))
Open "Data" tab and "What-If analysis" and "Goal Seek".
In "Set Cell", select "B1"
In "To Value", set the value you want to reach (0.6 in your sample)
In "By changing cell", set A1.
Click OK, see A1 becoming the expected result.

This might be a case for a graphical presentation:
where the formula in F2 (copied down) is =IF(E2>0,E2,0) and a Stacked Column has been applied.

Related

FCR Calculation for Number of calls vs Y / N responses

I'm currently looking at a way to calculate FCR data.
The goal is for the formula to look at what name is in column A, and then to see how many calls are made in B that either match Y or N and then the calculate it as an average in column F.
I've put a mock up of what the data looks like when entered and also in E and F where i'd like the actual outcome to be presented.
I've been trying to work with a Sumif/Countif this morning and have not been able to get it off the ground, any support would be great and i can also then use it for future learning.
do you guys think this is possible?
enter image description here
With Office365 you could use the following in E2:
=UNIQUE(A2:A9)
This spills the unique names.
In F2 you can than use a SUMIFS referencing the data and the spill:
=SUMIFS(B2:B9,C2:C9,"Y",A2:A9,E2#)/SUMIFS(B2:B9,A2:A9,E2#)
(Format these as percentage)

Excel- Need to ignore "±" and sometimes a "°" in a larger function

I have a series of spreadsheets that list design drawing dimensions. A1 is a number corresponding to a drawing, B1 is the dimension on the drawing, C1 is the actual dimension we encountered, D1 is the manufacturing error tolerance which is something like ±.005 or ± 1°. They vary between a few numbers on each drawing, and the drawings vary. E1 is a column that needs to say either Accept or Reject, reject is when the B1 dimension is more than the D1 away from the C1 value.
I inherited the spreadsheet with the function =IF(AND(C1<=(B1+.005), C1>=(B1-.005)), "Accept", "Reject"). This works, but I need to keep changing the .005 to values like .020 and 1° and I want to finish this faster than doing it all by hand. I would like to be able to drag in down the whole E column and have it fill out accept and reject accordingly.
I tried changing it (C1<=(B1+D1)) so it pulls from the tolerance, but get a value error because every tolerance has a ± in front of it. I tried adding MID to it, but I keep getting errors because I'm not quite sure how to incorporate it.
I couldn't find other help online because most people using MID are trying to extract characters, but I need the tolerances to stay the same in the D column. Avoiding errors from "°" would also be helpful, but that's only about 5% of the data and I deal with doing those manually if I have to. Kinda new to excel, still trying to really understand the intricacies and necessary syntax of the functions, so sorry if this is and easy one.
For the Mid I tried C1<=(B1+(MID(D1,2,4))) Which I know is very wrong. Thanks for any and all help!
Taking your approach:
=IF(AND(C1<=(B1+MID(SUBSTITUTE(D1,"°",""),2,LEN(D1))),C1>=(B1-MID(SUBSTITUTE(D1,"°",""),2,LEN(D1)))),"Accept","Reject")
Thanks pnuts
=IF(AND(C1<=(B1+MID(SUBSTITUTE(D1,"°",""),2,LEN(D1))),C1>=(B1-MID(SUBSTITUTE(D1,"°",""),2,LEN(D1)))),"Accept","Reject

Removing Lower/Upper Fence of outliers from input data to then be evaluated

What I have attempted:
AVERAGEIF(B11:V11,">+MEDIAN(B11:V11)")
What I am trying to do:
I would like to take the average of the upper half of given data. Elaborating more. I would like to find a formula that will allow me to remove a given lower fence of outliers and dissect the data then given to me. I would greatly prefer to maintain this formula within one cell "not grabbing different results from formulas within multiple cells".
Update:
Following through I found the solution.. I think.
One thing I should have explained further:
The data coming in replicating a typical sqrt function.
What I wanted to achieve is to capture the mean of the "plateau" of the data.
The equation I used was:
=AVERAGEIF(B3:B62,(">"&+TRIMMEAN(B3:B62,0.8)),B3:B62)
This was something I just copied and pasted. of course "B3" and "B62" are significant only for my application.
My rough explanation of the equation:
TRIMMEAN will limit the AVERAGE to the top 20%(">")(0.8) of the data selected. So for my application, this SHOULD give me a rough mean of the "plateau" of the data i would like to find the mean for.
This formula calculates the Median() of the range, then AverageIf() uses the median and only grabs values that are greater than or equal to >= the median ~ giving you the average of the 'top-half' of your values.
AVERAGEIF(A1:A10,">="&MEDIAN(A1:A10))
Hope this help!

Finding the absolute difference with positive and negative values

I have two columns. One with positive values and one with negative values. I need to find the absolute difference between the two columns.
What I am currently doing is the following: First of all, I edit both the columns to make all the values positive. Then I subtract the first column with the second column. I change any negative value to the positive one. Is this the same as the absolute difference?
Why not just use the ABS function
=ABS(B1-A1)
It sounds like what you're doing is actually
=ABS(ABS(B1)-ABS(A1))
which is not the same as
=ABS(B1-A1)
for example if you have -3 and 1 the first would give you 2 and the second would give 4. I don't know which one you want.
This works no matter which value is positive or negative:
=MAX(A1,B1) - MIN(A1,B1)
OK, so here's a pretty clunky workaround, but it is something where I can understand what's going on and works every time.
Here is my scenario where I needed to solve this problem. I had a system stock list showing 1 of these 10 of those but also showing -10 of these and 5 of those, and once entering my physical data from doing a stock take, I had pluses and minuses all over the place, so the data looked like this:
Physical stocktake value system value
0 0
1 0
1 2
0 -1
1 -1
Effectively all the different connotations of pluses and minuses.
so column 'a' is actual, column b is system
I created columns c,d,e,f ..... I warned you it was a little clunky, but it is sound in the result.
formula in column c = '=IF(A1>B1,A1+B1,A1-B1'
formula in column D = '=IF(B1+C1<>A1,A1-B1,C1)'
formula in column E = '=IF(D1>C1,C1,D1)'
Column E is the data you want, it rationalises all of the pluses and Minuses in your data to show a true difference (independent of positive and negative location) for the values you require.
Someone much cleverer than I will condense this down into a singular equation, but i read up on it, tried the current solutions/advise, and didn't have a clue what the techs were going on about, so came up with this faultless solution.
It does work and it s simply a transpose the A1's and B1's for your data content.
Hope it helps (a little).
I for one will check back, just to pick up on what the clever guys and gals come back with, just a case of life is to short to drive into this level of detail for a simple solution. Sometimes simple is best.
Yeah ok, set myself up for that one ..... so I'm simple, but I know what I'm doing and understand it ........

Interpolating data points in Excel

I'm sure this is the kind of problem other have solved many times before.
A group of people are going to do measurements (Home energy usage to be exact).
All of them will do that at different times and in different intervals.
So what I'll get from each person is a set of {date, value} pairs where there are dates missing in the set.
What I need is a complete set of {date, value} pairs where for each date withing the range a value is known (either measured or calculated).
I expect that a simple linear interpolation would suffice for this project.
If I assume that it must be done in Excel.
What is the best way to interpolate in such a dataset (so I have a value for every day) ?
Thanks.
NOTE: When these datasets are complete I'll determine the slope (i.e. usage per day) and from that we can start doing home-to-home comparisons.
ADDITIONAL INFO After first few suggestions:
I do not want to manually figure out where the holes are in my measurement set (too many incomplete measurement sets!!).
I'm looking for something (existing) automatic to do that for me.
So if my input is
{2009-06-01, 10}
{2009-06-03, 20}
{2009-06-06, 110}
Then I expect to automatically get
{2009-06-01, 10}
{2009-06-02, 15}
{2009-06-03, 20}
{2009-06-04, 50}
{2009-06-05, 80}
{2009-06-06, 110}
Yes, I can write software that does this. I am just hoping that someone already has a "ready to run" software (Excel) feature for this (rather generic) problem.
I came across this and was reluctant to use an add-in because it makes it tough to share the sheet with people who don't have the add-in installed.
My officemate designed a clean formula that is relatively compact (at the expensive of using a bit of magic).
Things to note:
The formula works by:
using the MATCH function to find the row in the inputs range just before the value being searched for (e.g. 3 is the value just before 3.5)
using OFFSETs to select the square of that line and the next (in light purple)
using FORECAST to build a linear interpolation using just those two points, and getting the result
This formula cannot do extrapolations; make sure that your search value is between the endpoints (I do this in the example below by having extreme values).
Not sure if this is too complicated for folks; but it had the benefit of being very portable (and simpler than many alternate solutions).
If you want to copy-paste the formula, it is:
=FORECAST(F3,OFFSET(inputs,MATCH(F3,inputs)-1,1,2,1),OFFSET(inputs,MATCH(F3,inputs)-1,0,2,1
(inputs being a named range)
There are two functions, LINEST and TREND, that you can try to see which gives you the better results. They both take sets of known Xs and Ys along with a new X value, and calculate a new Y value. The difference is that LINEST does a simple linear regression, while TREND will first try to find a curve that fits your data before doing the regression.
The easiest way to do it probably is as follows:
Download Excel add-on here: XlXtrFun™ Extra Functions for Microsoft Excel
Use function intepolate().
=Interpolate($A$1:$A$3,$B$1:$B$3,D1,FALSE,FALSE)
Columns A and B should contain your input, and column G should contain all your date values. Formula goes into the column E.
A nice graphical way to see how well your interpolated results fit:
Take your date,value pairs and graph them using the XY chart in Excel (not the Line chart). Right-click on the resulting line on the graph and click 'Add trendline'. There are lots of different options to choose which type of curve fitting is used. Then you can go to the properties of the newly created trendline and display the equation and the R-squared value.
Make sure that when you format the trendline Equation label, you set the numerical format to have a high degree of precision, so that all of the significant digits of the equation constants are displayed.
The answer above by YGA doesn't handle end of range cases where the desired X value is the same as the reference range's X value. Using the example given by YGA, the excel formula would return #DIV/0! error if an interpolated value at 9999 was asked for. This is obviously part of the reason why YGA added the extreme endpoints of 9999 and -9999 to the input data range, and then assumes that all forecasted values are between these two numbers. If such padding is undesired or not possible, another way to avoid a #DIV/0! error is to check for an exact input value match using the following formula:
=IF(ISNA(MATCH(F3,inputs,0)),FORECAST(F3,OFFSET(inputs,MATCH(F3,inputs)-1,1,2,1),OFFSET(inputs,MATCH(F3,inputs)-1,0,2,1)),OFFSET(inputs,MATCH(F3,inputs)-1,1,1,1))
where F3 is the value where interpolated results are wanted.
Note: I would have just added this as a comment to the original YGA post, but I don't have enough reputation points yet.
alternatively.
=INDEX(yVals,MATCH(J7,xVals,1))+(J7-MATCH(J7,xVals,1))*(INDEX(yVals,MATCH(J7,xVals,1)+1)-INDEX(yVals,MATCH(J7,xVals,1)))/(INDEX(xVals,MATCH(J7,xVals,1)+1)-MATCH(J7,xVals,1))
where j7 is the x value.
xvals is range of x values
yvals is range of y values
easier to put this into code.
You can find out which formula fits best your data, using Excel's "trend line" feature. Using that formula, you can calculate y for any x
Create linear scatter (XY) for it (Insert => Scatter);
Create Polynominal or Moving Average trend line, check "Display Equation on
chart" (right-click on series => Add Trend Line);
Copy the equation into cell and replace x's with your desired x value
On screenshot below A12:A16 holds x's, B12:B16 holds y's, and C12 contains formula that calculates y for any x.
I first posted an answer here, but later found this question

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