No matter how little or how much you use me, you change me every month. What am I? Share Tweet Answer A calendar
Charles walks over a railway-bridge. At the moment that he is just ten meters away from the middle of the bridge, he hears a train coming from behind. At that moment, the train, which travels at a speed of 90 km/h, is exactly as far away from the bridge as the bridge measures in length. Without hesitation, Charles rushes straight towards the train to get off the bridge. In this way, he misses the train by just four meters! If Charles had rushed exactly as fast in the other direction, the train would have hit him eight meters before the end of the bridge. What is the length of the railway-bridge?
My skin is tough, yet I'm not a star. In the jungle, a giant of the land, with a gentle face. What am I?
The numbers 1 up to and including 16 can be placed in sequence in such a way, that the sum of each two consecutive numbers is a square. How should this be done?