A teacher is to form two groups of 4 students from a class of 3 boys and 4 girls for consultation session. three of the girls, ivy, tamie and cassy are good frens. find the prob that either ivy or tamie is in the same grp as cassy.
i remove cassy from the group 1st. then (2C1x 5C2)/7C3.
but this is wrong. can u guys help me out?