Hi!

Yesterday we had a exercise in geometry, it was said:

A regular triangle pyramid with all of its edges 5cm long. There is a smaller triangle that is cutting the edge in half. Need to calculate volume and full surface area.

Here is a small picture of the figure -

http://img337.imageshack.us/img337/9536/pyrl.jpg

As far as I could figure out this one, the bigger triangle is 2 times bigger then the smaller one, area is 2^2 times bigger.