Hi,
May a person answer “amen” to a bracha if they didn’t hear the whole thing?
If yes, what part must they hear in order to answer “amen”?
Answer:
If one is aware which bracha is being recited and when it ends, even if he does not hear the end of the bracha he may recite amen.
Sources:
O:C 124:8, M”B 31-33