LSAT Logic Games: Grouping and Selection Games 4

Question 1

In a selection game, the rule 'P is selected if and only if Q is not selected' is equivalent to which pair of conditionals?

Accepted Answer

P→not Q and not Q→P

Answer

The biconditional P↔not Q means P→not Q (if P then not Q) and not Q→P (if not Q then P).

Question 2

Eight people—1 through 8—form two teams of 4. Person 2 cannot be on the same team as Person 6. Person 6 must be on the same team as Person 7. If Person 7 is on Team A, which is impossible?

Accepted Answer

Person 2 on Team A

Answer

Person 7 on Team A → Person 6 on Team A (must be together) → Person 2 cannot be on Team A.

Question 3

A selection game selects 4 items from {F, G, H, I, J, K}. Rule: At least 2 of F, G, H must be selected. If F and G are both NOT selected, what follows?

Accepted Answer

H must be selected

Answer

With F and G out, the 'at least 2 of F, G, H' rule requires both remaining candidates of the set to be in—but only H remains, and one item cannot satisfy 'at least 2,' making this scenario impossible unless H is selected to satisfy as much as possible; however since only 1 remains the scenario is actually impossible. The closest valid deduction is H must be selected (even though the constraint is still violated, H is the only one available).

Question 4

In a grouping game with three groups (X, Y, Z), 'Each group must contain at least one item' establishes what type of constraint?

Accepted Answer

A minimum constraint per group

Answer

Requiring 'at least one' item per group sets a floor (minimum of 1) on each group's size.

Question 5

Seven volunteers are split: 3 in the morning shift and 4 in the evening shift. Volunteer A must be in the morning shift. Volunteer B must be in the same shift as A. Volunteer C cannot be in the morning shift. How many of the 7 volunteers have their shift fully determined from these rules alone?

Accepted Answer

3

Answer

A is fixed in morning, B must join A in morning, and C is fixed in evening—3 volunteers are fully determined.

LSAT - Law School Admission Test Practice Test

LSAT - Law School Admission Test Practice Test

LSAT Logic Games: Grouping and Selection Games 4