4. Let S be a subset of the set of numbers {1, 2, 3, ..., 2008} which consists
• The use of rulers and compasses is allowed, but
of 756 distinct numbers. Show that there are two distinct elements a, b
calculators and protractors are forbidden.
of S such that a + b is divisible by 8.
• Start each question on a fresh sheet of paper. Write
on one side of the paper only. On each sheet of
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