Problem K. 157. (February 2008)
K. 157. Street lamps in a village are placed at equal intervals along the road. I observed that during 1 minute I passed as many lamp posts as 1/12 of my speed in km/h. Given that I was moving at a uniform speed and I started and finished counting when I was midway between two posts, calculate the separation between lamp posts.
Deadline expired on March 10, 2008.
Sorry, the solution is available only in Hungarian. Google translation
Megoldás. Tegyük fel, hogy egy perc alatt x lámpát hagytam el, ekkor 1 óra alatt 60x-et hagynék el, és a sebességem 12x km/óra lenne. Ezek alapján 12x kilométer alatt 60x lámpát látnék, azaz 1 km alatt ötöt, tehát a lámpák 200 méterre vannak egymástól.
121 students sent a solution. 6 points: 105 students. 5 points: 4 students. 4 points: 5 students. 3 points: 3 students. 2 points: 2 students. 1 point: 1 student. Unfair, not evaluated: 1 solution.