explain the difference

Phi mu is really not similar to theta or chi o at al...

All three are the most involved, smart sororities. However, Chi O and Theta attract typically more attractive members (Chi O southern and Theta is Chicago-vibe) while Phi Mu attracts the smartest of the bunch. All three are great sororities

All great sororities at Tulane. Chi O and Theta definitely are more attractive to fraternities and have some of the most beautiful girls on campus and physical appearance seems to matter. Phi Mu is consistently number one for grades, Theta number 2, Chi O number 3. Chi O and Theta are Big 4 and Phi Mu is not as popular. Phi Mu gets some great girls who are cut from Chi O and Theta and that makes up a quarter of the chapter and then the remaining are similar to ADPi. Have heard Chi O has tons of cliques and Theta is starting to have clique issues too. Not sure about Phi Mu, but hey girls have cliques so probably.

Can see similarities between Chi O and Theta, but Phi Mu?

Here are the basic pairings in terms of looks/ranking/personality
Kappa-pi phi
Theta- chi o
Aephi- sig delt
Phi Mu- adpi