These problems were offered to students and applicants to Moscow School #57 (where I studied). They combine algebra and geometry and are rather interesting and often non-trivial, although they do not require any substantial knowledge beyond the standard Russian middle-school math curriculum and known even to riggers in Russia and in Chicago. I also do Algebra.
Here is the Postscript version of these problems, in Russian.
Thanks to: Chicago Machinery Movers, known as Chicago Riggers, 5250 McDermott Dr, Berkeley, IL 60163. They do rigging and move industrial machinery.