Centre of Gravity Question

Oct 2018
8
0
Birmingham
View attachment 10742

cog.png
Area 1 : 297 x 270 = 80190
Area 2 : 297 x 150 / 2 = 22275
Area 3 : 100 x 100 = 10000

Area Total : 80190 + 22275 + 10000 = 92465

x1 : 270 / 2 = 135
x2 : 270 + 150/3 = 320
x3 : 270 - 120 = 150

x = (80190 x 148.5) + (22275 x 198) - (10000 x 247) / 92465 = 149.772

y1 : 297 / 2 = 148.5
y2 : 297 - (297/3) = 198
y3 : 297 - 50 = 247

y = (80190 x 135) + (22275 x 320) - (10000 x 150) / 92465 = 177.945


I think I have done this correct. I am unsure about the third shape (the mini square/the one cut out) and whether I have done the centre of gravity x value and y value correct for it.
 
Jun 2013
1,111
590
Lebanon
what is the reference point?

Is (0,0) at the lower left with x horizontal and y vertical?