The square contains digits 1 to 9. Start at the star, follow a line and write the digits passed. The example gives 42685. Which line gives the largest number?
The map shows stations A, B, C. Tours A–Zoo–Port–A, B–Park–Zoo–B, C–Port–Park–C have lengths 10, 12, 13 km. The Zoo–Park–Port–Zoo tour is 15 km. How long is the shortest A–B–C–A tour?
Ronja has four white tokens and Wanja four grey tokens. Starting with Ronja, they alternate placing tokens to form two piles. Which pair of piles is impossible?
Each pirate tells the truth about exactly one of the two quantities, coins and diamonds, and lies about the other. Their statements are shown. What is the total number of coins and diamonds?
Pirate 1: 8 coins and 6 diamonds. Pirate 2: 7 coins and 4 diamonds. Pirate 3: 7 coins and 7 diamonds.
Trains between X and Y can pass only on the double-track section. At constant speeds, X to Y takes 180 minutes and Y to X takes 60 minutes. Two trains can start simultaneously from opposite ends without colliding. Which line is possible?