LSAT Logic Games: Grouping and Selection Games 5 — Questions and Answers
Question 1: Nine items are distributed into 3 groups of 3. Item X and Item Y must be in the same group. Item Y and Item Z must be in different groups. If X is in Group 1, which must be true?
- Z is in Group 1
- Y is in Group 2 or 3 (Correct answer)
- Z is in Group 1 with X
- Y is in Group 1 and Z is in Group 1
Correct answer: Y is in Group 2 or 3
X in Group 1 forces Y to Group 1; Y and Z cannot share a group, so Z must be in Group 2 or 3—meaning Y is in Group 1 (not 2 or 3), but Z is not in Group 1, confirming Z is in Group 2 or 3.
Question 2: A selection game picks 4 from {A, B, C, D, E, F, G}. Rule: 'If A is selected, then B is selected. If B is selected, then C is selected.' If C is NOT selected, what follows?
- A may still be selected without B
- B and A are both not selected (Correct answer)
- Only A is not selected
- C's exclusion has no effect on A or B
Correct answer: B and A are both not selected
Contrapositive chain: not C → not B (from B→C), and not B → not A (from A→B), so both A and B must be excluded.
Question 3: In a grouping game, 'the number of items in Group 1 is greater than the number in Group 2' restricts distributions to which kind?
- Distributions where Group 1 and Group 2 are equal
- Distributions where Group 1 has more items than Group 2 (Correct answer)
- Distributions where Group 2 has more items than Group 1
- Distributions where both groups have the same total
Correct answer: Distributions where Group 1 has more items than Group 2
The constraint directly states Group 1 must have more items, eliminating equal or Group-2-majority distributions.
Question 4: Seven candidates—P, Q, R, S, T, U, V—are selected or rejected for a panel. Exactly 4 are selected. Rule: P and Q are either both selected or both rejected. Rule: R is selected if and only if S is rejected. If P is rejected, which is a valid selection?
- Q, R, S, T
- Q, R, T, U
- P, R, T, U
- Q, S, T, U (Correct answer)
Correct answer: Q, S, T, U
P rejected → Q rejected (both-or-neither rule); R selected ↔ S rejected—so Q, S, T, U works with R excluded (S in means R out).
Question 5: Which of the following best describes an 'in/out' grouping game on the LSAT?
- Items are ranked from best to worst
- Items are assigned to one of two categories: selected or not selected (Correct answer)
- Items are placed in a fixed sequence
- Items are distributed among three or more groups of equal size
Correct answer: Items are assigned to one of two categories: selected or not selected
An in/out game divides elements into exactly two buckets: those chosen (in) and those not chosen (out).
Question 6: A game selects 3 from {H, I, J, K, L}. Rule: If H is selected, exactly one of I or J (not both) is selected. If H is selected and I is selected, what must be true?
- J is also selected
- J is not selected (Correct answer)
- K and L are both selected
- The selection is invalid
Correct answer: J is not selected
H selected with I selected triggers 'exactly one of I or J,' meaning J cannot also be selected.
Question 7: In LSAT logic games, making a 'global deduction' before tackling individual questions is valuable because:
- It eliminates the need to read question stems
- It reveals constraints that apply to every valid arrangement (Correct answer)
- It always identifies the correct answer immediately
- It only helps for ordering games, not grouping games
Correct answer: It reveals constraints that apply to every valid arrangement
Global deductions derived from combining rules narrow the solution space for all questions in the game.
LSAT Logic Games: Grouping and Selection Games 5
Nine items are distributed into 3 groups of 3.
Item X and Item Y must be in the same group.
Item Y and Item Z must be in different groups.
If X is in Group 1, which must be true?