N _ T
1 2
S _ C _ N D S .
T H _ R _
_ R _
7
S _ G M _ N T S
F R _ M
T H _
F _ R S T
F L _ G
T _ T
T H _
_ _ G H T H ,
_ N D
1 1
F R _ M
T H _
F _ R S T
T _
T H _
T W _ L F T H .
H _
R _ N S
_ _ C H
S _ G M _ N T
_ N
8 / 7
S _ C _ N D S ;
T H _ R _ F _ R _ ,
1 1
S _ G M _ N T S
T _ K _
8 8 / 7 =
1 2
4 / 7
S _ C _ N D S Clue
NOT 12 SECONDS. THERE ARE 7 SEGMENTS FROM THE FIRST FLAG TOT THE EIGHTH, AND 11 FROM THE FIRST TO THE TWELFTH. HE RUNS EACH SEGMENT IN 8/7 SECONDS; THEREFORE, 11 SEGMENTS TAKE 88/7= 12 4/7 SECONDS THE FLY WOULD HAVE TRAVELLED 90 MILES. THE TRAINS ARE 100 MILES APART, AND THE TRAINS ARE TRAVELLING TOWARD EACH OTHER AT 40 AND 60 MPH, THE TRAINS WILL MEET IN ONE HOUR. THE FLY WILL HAVE BEEN FLYING FOR AN HOUR AT 90 MPH AT THAT POINT, SO THE FLY WILL HAVE TRAVELLED 90 MILES THE MESSENGER HAS TO HAVE TRAVELED 2 KM. IT DOESN'T MATTER WHAT SPEED THEY WALKED AT. AT THE BEGINNING OF THE PUZZLE, THE LINE IS 1 KM LONG. THE GENERAL IS THEREFORE 1 KM AHEAD OF HIM. THE MESSENGER MUST THEREFORE TRAVEL MORE THAN 1 KM TO REACH THE GENERAL. SINCE THE LINE MOVES 1 KM FORWARD, THE END IS WHERE THE BEGINNING WAS. EVEN IF HE WALKED 1.5 KM TO THE GENERAL, HE ONLY HAS TO WALK 0.5 KM TO GET BACK TO THE END OF THE LINE. IT GOES FASTER GOING BACK, BECAUSE NOW THEY ARE COMING TOWARDS HIM, AND NOT GOING AWAY YES, THERE IS A POINT ALONG THE PATH THAT THE MONK OCCUPIES AT PRECISELY THE SAME TIME ON BOTH DAYS. IF YOU ASSUME THAT THE THERE ARE TWO MONKS, ONE DOES THE ROUTE FROM THE TOP, AND THE OTHER FROM THE BOTTOM. AT SOME POINT, THEY MUST MEET. THERE'S YOUR POINT