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1. I have an equation and in it are 2 terms, 1 being the quadratic mean, or so says in the lecture notes. It's to do with a size distribution of a grain of a substance. The term given fr the Qm is:
Z*(Integral between 0 - 1) X^2 dF

Where Z are all the other terms in the equation which are constant, and X is size. I know Qm is sqrt( 1/n (a^2 + b^2 ... )) but how does this also become?

My size values are in a table which contains Size, and then a cumulative frequency.

If more information is needed I could provide the table or the full equation.

So far I have tried using thw Qm equaton and it doesn't give me the right answer. I have also done the integral getting x^2 F but I don't see how that helps me, do I then just do x^2 F for each one and then divide by n and root?
2. anyone/

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Updated: December 27, 2010
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