Calculating y-Coord of Center of Mass in Unique Shape

[phsyics_197]

Homework Statement

____
l _ l
l_l l_l

Find the y-coordinate of the center of mass. Each side l / _ is length a.
I got an answer of 1.25a, but that isn't right.

Homework Equations

The Attempt at a Solution

Area of each section * x-coordinate of center of mass. (the area missing is negative)
Then divided by the total area

 

[tiny-tim]

Welcome to PF!

Hi phsyics_197! Welcome to PF!

____
l _ l
l_l l_l

Find the y-coordinate of the center of mass. Each side l / _ is length a.
I got an answer of 1.25a, but that isn't right.

(hmm … I can see from the "QUOTE" box that that's supposed to be two squares on level 0, and three squares on level one)

Show us how you got 1.25, and then we can see what went wrong, and we'll know how to help!