maths :D

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ok am this is a request to all those maths ppl am there is a set of data on the top left (note just look at the first 2 columns the points for these results are in blue and not pink) the name of alcohol is taken as ethanol is x=1, propanol is x=2 and so on and the y is those negative numbers not with thap’s help i have been able to get excel to display the formula of the line of best fit in Y = 747.8x - 494.37 format i need to know the formula and the method for how excel got this if any one can help it will be appreciated.

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Is it simple linear equation ???
then whats the need of formulae ???

X and Y two variables, with a constant

Y = 747.8x - 494.37

if you want to fit the values, reduce the graphs ratio with the original values

in case i havnt understood the problem, PM me the excel file.. ill look into it..


Dont think "you can" know "you can"
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flamez yaar there is a statistical formula to work the Y= bla bla stuff out . and i have the answer and i know if i put X in to the equation i will get an answer . i need to show how i got that equation

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isn't it just y=mx+b, where m is the slope of your line (slope=m=(y2-y1)/(x2-x1))
and be is the y-intercept

where you line intercepts the graph at the y-axis

Waleed

y=mx+b

or in the case above y=-mx-b

b is the intercept on the y axis
m is the slope.

in order to find m you need to plot the graph on crossed axes in order to find the delY and delX points m=dely/delx

in your case above choochay del y is (-1367.3)-(-5293.6)=3296.3 over del x is 1-6=5

so m= del y over del x=-785.26 my value is a little out coz i eyed in the values.

[This message has been edited by Rolo_Tomassi (edited February 22, 2002).]

ditto to hayaa and rolo

The reason you are probably getting contradicting answers is b/c the points plotted do not give you a linear line. It’s the best fit line. And since the slope in this case is created by the computer, you don’t know which two points were used to calculate that. You better option would be to take points on your own and calculate the slope as hayaa and rolo have suggested. Take two points that when connected are a straight line, a line that best fits to the rest of the points as well. Do it by yourself and not the comp

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at last thank u sehar baji

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some who knows wat they r talking about thank u sehar

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…the rest

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oh yeak this parhaee.
i dont like studies on line

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