Mind-meltingly difficult puzzle has 4 friends, a bridge and zombies – can you solve it?

 Mind-meltingly difficult puzzle has 4 friends, a bridge and zombies - can you solve it?

Taking that internship in a remote mountain lab might not have been the best idea. Pulling that lever with the skull symbol just to see what it did probably wasn’t so smart either. But now is not the time for regrets because you need to get away from these mutant zombies…fast. Can you use math to get you and your friends over the bridge before the zombies arrive? Alex Gendler shows how. Watch this TED-Ed Lesson below.