25x6=150

Run 400
25 burpees
x 6

With some of our work it's best not to look at the big picture, take it round by round. The workout is a task, it needs to be chipped away, metre by metre, burpee by burpee.
The first two rounds are worst if you let it loom ahead, then round three comes around, and you're half way, then four appears out of the fog of the burpees, after that there's only fifty burpees, you can do fifty burpees's.