- Fri May 18, 2018 6:19 pm
#45790
This question gave us the local rule that Wendy must be included in two of the three groups. Since there are three groups, there are only three possible pairs of groups that where can place Wendy.
The first possibility, placing Wendy in M and J, would violate the rules. Since whoever presents on M must also present on S, Wendy cannot be placed only in the M and J groups.
The second possibility would be to place Wendy in the M and S groups, but not the J group. This would mean that Rita may not be placed in those groups, since Rita and Wendy may not both be placed in S. Rita then has one option: J. Since Rita must present, we can infer that Rita is in the J group. George may be placed in any group.
The final possibility would be to place Wendy in the J and S groups, but not the M group. Again, Rita would not be allowed in the S group since W is already there. Additionally, Rita may not be placed in the M group, since that would force her into the S group as well, due to the third rule. Rita then would have to be placed in the J group. George then would have to go at least into the M group, since no other student can, and the scenario mandated at least one student per subject. He would then also be placed in the S group because of the third rule. George may be placed in the J group, but that is not necessary.
The correct answer choice was (D). the inference that you can get by testing out all possible placements for Wendy is that no matter where Wendy is placed (in the M and S groups, or in the J and S groups), Rita must be placed in the J group.