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View Full Version : HELP ASAP! Can't understand the current material of my Statistics Class. (Equations)



OT-1
11-04-2015, 02:09 AM
Greetings everyone!
I'm a new member of this community in search of people that can help me understand the class material.
This is all I got at the moment:

http://www.freemathhelp.com/forum/attachment.php?attachmentid=5900&stc=1

That's the formula.
After making all the equation in the data table, it's supposed to go like this.


52 = 6a + 21 b1 + 30 b2
240 = 21a + 91b1 + 111b2
251 = 30a + 111b1 + 180b2

I know some multiplication and division must be done, but how?
Sorry if this isn't really statistics, but is something that my Statistics professor is giving me at the time.
Please help me if you can.
Thank you!

ksdhart
11-04-2015, 01:03 PM
You have three variables in three equations, so that's a system that you can definitely solve. My starting point would be to define new temporary variables. Let b1 now be called b and let b2 now be called c. Rewrite and label the three equations:

6a + 21b + 30c = 52 (Row 1)
21a + 91b + 111c = 240 (Row 2)
30a + 111b + 180c = 251 (Row 3)

What if you divided Row 1 by 6? So this would be the new Row 1:

a + (21/6)b + 5c = (26/3)

Now what if you let Row 2 = (Row 2) - 21*(Row 1) and Row 3 = Row 3 - 30*(Row 1)? What do you get? Do you see where I'm going with this?