Consider a standard twelve-hour clock whose hour and minute hands move continuously. Let m be an integer, with 1≤m≤720. At precisely m minutes after 12:00, the angle made by the hour hand and minute hand is exactly 1∘. Determine all possible values of m.
Prove that when three circles share the same chord AB, every line through A different from AB determines the same ratio XY:YZ, where X is an arbitrary point different from B on the first circle while Y and Z are the points where AX intersects the other two circles (labelled so that Y is between X and Z ).
Let S be a set of n points in the plane such that any two points of S are at least 1 unit apart. Prove there is a subset T of S with at least n/7 points such that any two points of T are at least 3 units apart.