FREE
AUTUMN 2025
Disaster struck the dog world: the Golden Bones of Professions have vanished—magical artifacts that helped dogs remember what they do. Without the bones, the chef-dog is making slipper soup, the builder-dog is putting a kennel on a garage roof, and the astronaut has mistaken a rocket for a giant tin can.
The devious Fake Science Cat couldn’t stand the dogs’ success and hid the bones in the most unexpected places. Now you can reach them only through riddles, goofy trials, and true cleverness.
Setting off on the quest are: Tormund, the Brabançon architect; Nebula, the greyhound astronaut; and Bonya, the Pomeranian barista. They believe that, with the kids’ help, they’ll recover the bones and restore order to the professions.
Mathematical
Online Olympiad
Pythagorean Trousers
TASKS FOR AGES 10-11
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After clicking the "Start" button, the timer will start, and you will have 60 minutes to complete the quiz.
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Spaceport “Laika-1” 🚀
The dogs are preparing a rocket launch but mixed up spacesuits with grooming coveralls. One pup put a bowl on his head instead of a helmet, and another is “checking” the engine by sticking his tail in it. To claim the bone, solve the cat’s first riddle and send the “Bowlship” into orbit.
Greyhound Nebula noticed that in the year of her first spaceflight, in April, three Thursdays fell on odd dates. On what day of the week did Nebula fly if it happened on April 16?
Clinic of Tailed Doctors
Fox cub Pif asked Dr. Lloyd how to eat more fruit —and got a puzzle instead! Help solve it to free Lloyd from the nasty cat’s spell.
On Monday, September 1, Little Fox Pif decided to start fitness and go to the gym every Monday and Thursday. After each workout, he eats 500 grams of fruits from a huge bag of fruits. On all the other days of the week, he puts 200 grams of fruits into the bag. By how many grams will the weight of the bag change by March 1 of the next year, if the year is a leap year? Enter only the number.
Bakery “Paw & Bun”
The puppy-chef bakes everything in the shape of bones, paws, and tails. To win back the golden bone, you’ll need to solve a riddle.
The giant "Bone" cake consists of many identical tiers. To climb from the 10th tier to the 20th tier, a Spitz needs 100 seconds. The dogs decided to add 2025 more tiers to the cake. After that, the time to climb from the first tier to the very top reached 40,000 seconds. How many tiers were in the cake originally? Enter only the number.
Architecture Bureau “Kennel & Partners”
The dog architects decided to build skyscrapers, but everything keeps turning out kennel-shaped. One project is "Kennel-Eiffel Tower," another is "Kennel on the Moon." To move on, help restore the blueprint and explain to the architects that not everything in the world has to look like a kennel.
Architect Torik drew 10 straight lines so that several squares appeared. Not all of them are the same size. The maximum possible number of squares with 10 straight lines was achieved. How many squares does Torik have? Hint: Count the squares by size. Start with the smallest ones, then bigger, and so on. Enter only the number.
Music Studio “Bark Major” 🎶
The dog musicians have lost the beat: the trumpet barks, the drum whimpers, and the guitar is sniffing the speakers. The last bone is with the basset conductor, who conducts with his tail. To get it back, you must perform the first dog symphony in history—without any "barks" or "growls."
Using drumsticks, the dog musicians laid out the equation 4 + 9 = 29 (see picture). But it’s wrong! What is the smallest number of sticks you need to move to make the equation correct? Add this number to the result you get on the right-hand side. Enter that number.
Woo-hoo! The dogs can finally work in peace again — all thanks to you and the Pythagoras Maths Charity!
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