Answer :

Solution :

Case 1: The number of teams with 2 members can be formed with Q as a member

Out of the 2 members, one member is Q and another member can be selected from the remaining three members.

The number of teams can be formed$=3_{C_1}=3$

Case 2: The number of teams with 3 members can be formed with Q as a member

Out of the 3 members, one member is Q and another 2 members can be selected from the remaining three members.

The number of teams can be formed$=3_{C_2}=3$

Case 3: The number of teams with 4 members can be formed with Q as a member

Out of the 4 members, one member is Q and another 3 members can be selected from the remaining three members.

number of teams can be formed$=3_{C_3}=1$

Now, the total number of teams can be formed = 3 + 3 + 1 = 7