It would not have the same rights as a natural human. Presumably, if such a line were drawn, there would be a good reason for not recognizing a below 70% pass rate rather than arbitrarily choosing that number.

This is a more general problem with any sort of cutoff that segregate a continuous quantity into separate groups. (Should someone who is 20.9 years old be legally recognized as an adult? Is there really a difference between the mentally retarded person with a 69.9 IQ and the person who scored a 70.1?)