Dinosaurs lived between 230 and 65 million years ago. Dinosaurs varied greatly in size, from the giants that were the size of a truck to the smaller dinosaurs some of which were the size of a small bird. Dinosaurs are now extinct and much of our knowledege is gained from dinosaur fossils.
See if you can solve these four more difficult arithmagons.
The aim of an arithmagon is to work out which numbers go in the empty circles. The numbers in the square boxes are made by adding together the numbers in the circles either side. For example, if the number in the square box was 10 you could try 6 and 4, but the numbers must also add up on the other edges, making this more difficult than it first appears.