#13 - Global, Must Be True

[Dave Killoran]

Complete Question Explanation
(The complete setup for this game can be found here: lsat/viewtopic.php?t=6605)

The correct answer choice is (D)

As discussed during the analysis of the first rule, T must always run in one of the four races. Thus, answer choice (D) is correct.

[mollyquillin]

Why must the coach select T to run in this race? I'm confused why the answer is not A (which is that Q must be selected). Could someone please explain?

[Paul Marsh]

Hi Molly!

So we know from our Setup that 4 of the 5 runners are selected. That means 4 of the people will run, and only 1 will sit out.

Our first Rule tells us that if Q is selected to run, then T must also be selected and run in the very next race. So whenever Q is selected, T must be selected too! We can write this as a conditional if that helps:
Q T
And the contrapositive of that conditional would be:
NOT T NOT Q

So if T sits out, then that means Q has to sit out too. But remember what I said up above: we know from our Setup that 4 people have to run, and only 1 can sit out. So it's not possible for T and Q to both sit out! That means T always has to be selected.

Hope that helps!