Question:
What is considerd ‘tifilah betzibur’, do ten people together have to pray, or is it enough that there are ten of them, of whom most of them begin the prayer of ‘amidah’ and in a few moments the rest join in?
Answer:
When there are ten of them, most of whom begin the prayer of ‘amidah’, and only after a few moments are joined by the rest of them, is considered a prayer in public.
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