Reply To: Pi, eruvin 13b-14a

PBA: I disagree. The Gemara has a concept that we can approximate sometimes (Lo Dak; see around Sukkah Daf 8), but always only L’Chumra. We need a Passuk to tell us that we can always assume that pi is 3, even though it will have Nafka Minos that are L’kula as well.