Just put this , 13.20/6 which is 2.20 so thats 2.20$ a bowl.
also you could , 2.20*6=13.20 , thats still 13.20 (2.20)
all together this means the unit rate in dollar is 2.20 for bowl , per bowl. for Melinda because she bought them for 13.20
i hope this helps.