Author: thephoenix Posted: Tue Jan 26, 2010 10:00 pm (GMT -8) IMO C i just tried by plugging sme selected no’s( and a bit of assumptions) to meet s1) we need p+n = 5k+1(where k is int) there can be n no. of combination hence s1) alone insuff to meet s2) we need p-n=3K+1 same as s1) insuff… combining u will come to knw that no,s like p=5 and n=1; p=20 and n=1are satisfying bth the statements and remn is 9 for bth the cases now time to assume that it holds true for all such no’s hence C sorry for such a vague reply but on exam such tricks will play a role of crocin to keep your headache away

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Data Sufficiency :: RE: hard problem from gmatprep,help