Stats: Need help understanding where the sum of x^2 comes from

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The discussion revolves around understanding the calculation of the sum of squares, specifically Sum(x^2). The user is confused about how to derive values like 2431.72, 4901.66, and 3252.44 from their data. It is clarified that to find Sum(x), one must add the values directly, while for Sum(x^2), each value should be squared first and then summed. The conversation emphasizes the importance of correctly applying these mathematical operations to obtain the desired results. Understanding these steps is crucial for accurately performing statistical calculations.
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Homework Statement



I have no idea where the sum of x^2 comes from, from the information I posted. I know it must be something pretty simple but its completely going over my head. In the picture that I've attached, I am wondering where the 2431.72, 4901.66, and 3252.44 come from. Thank you for any help.


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What did you try to get Sum(x)? Sum(x^2)?
 
SteamKing said:
What did you try to get Sum(x)? Sum(x^2)?

I tried squaring x, but obviously that is not correct.
 
Did you try, you know, adding up the columns of figures? That's what Sum(x) means. The other one is trickier: you've got to square each number, and then add them up.
 
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