The pieces with the same color in left figure have the same size as in the ones in the right figure. In the right image the pieces are only ordered differently. How to explain the hole in the right image?

Can you connect all nine dots with only four straight line segments without losing contact with the paper while drawing?

Mansi is a language of a Siberian tribe and has about 3000 speakers. Here some number in the Mansi language:
8: nollow, 15: atxujplow, 49: atlow nopel ontellow, 50: atlow, 99: ontelsat ontellow, 555: xotsatn xotlow nopel at, 900: ontellowsat, 918: ontellowsat nollowxujplow.

What is the meaning of the following words: atsatn at, nolsat nopel xot, ontellowsatn ontellowxujplow? And how to say 58, 80, 716 in the Mansi language?

Problem Language Olympiade 2005