The students were graded based on correctness
of solution to the problems.  For example in Problem
3, the students were required to provide counterexamples
to the false statements (1) and (2)
and a simple one line proof for (3).
Each subproblem
carried 10 points each.
Formal proofs
were given 10 points whereas informal proofs or incorrectly
written proofs earned partial credit.