It is estimated that 20 % of students change programs within their first year . Given a 1,000 third - year student sample to determine P ( more than 250 ( 25 % ) students changed their program during their first year ) , can we assume the p - bar distribution is normal ? No because we do not have enough information . Yes , because np > 5 and n(1 - p) > 5 . Yes , because .000 > 30 Yes , because 50 > 30 .