Don't ask me why, but I have an odd mental block that stops me remembering the (incredibly simple) equation for figuring out the total reps performed in a ladder; I always end up on @joel.snape's website refreshing my memory, so here's a graphic I put together in the hopes it may help some of you guys and cement the equation in my brainbox.
Total reps performed when n=last round you performed (on a a straight forward ladder starting at 1 and adding an additional rep each time).
E.g. A 1-10 ladder would equal 10 x (10+1) / 2= 55 total reps.
Now it's time for you to do 'death by burpees' and try it out for yourself.