Hi, my friend helped me out with a problem before he had to go somewhere:

http://i51.tinypic.com/nwal8h.png

He told me that since it says '6 congruent shapes implies that the height is 2/3 of the width.' I never got that. After that though, it's basic linear equations, I ended up with 100 centimeters. But how did he come up with the height = 2/3 width thing?