3 ms·

I don't see what's so hard about that one, it's a simple infinite sum.

• jameshart 12y ago
  There's an easier way than an infinite sum.
  • Khao 12y ago
    40mph + 60mph = 100mph, so they will travel for 2 hours before they hit each other. The bird flying at 100 mph for 2 hours will travel 200 miles.
  • thesteamboat 12y ago
    anon4 is referencing one of the tellings of this story where famous scientist [usually Von Neumann] is given this problem as a brainteaser and responds instantly having done it the `hard way'. http://mathforum.org/dr.math/faq/faq.fly.trains.html http://mathforum.org/dr.math/faq/faq.fly.trains.html