premise: A group of numbered participants walk down the street together.
hypothesis: A group walks down the street.
explanation_1: a group of participants who walk down the street
explanation_2: group of numbered participants walk can be inferred as group.
explanation_3: The numbered participants is simply more detail provided.  In both a group walks down the street, whether on not "together" is specified.
premise_logic: exists e1 e2 s1 x1 x2 x3.(n_street(x3) & a_together(s1) & Manner(e2,s1) & down(e2,x3) & Actor(e2,x1) & v_walk(e2) & of(x1,x2) & n_participant(x2) & Theme(e1,x2) & v_number(e1) & n_group(x1))
hypothesis_logic: exists e1 x1 x2.(n_street(x2) & down(e1,x2) & Actor(e1,x1) & v_walk(e1) & n_group(x1))