This is an explanation of the second logic game from Section II of LSAT Preptest 38, the October 2002 LSAT.
Frank, Gladys, and Leslie (F, G, L) are volunteers at a farm exhibition. Each of them will demonstrate two out of these six farming tasks: harvesting, milling, plowing, spinning, threshing, and weaving (H, M, P, S, T, W). You need to use the rules to determine who can demonstrate each task and what order they will present in.
Game Setup
This game is a mix of linear and grouping. We have to figure out which tasks the volunteers demonstrate, and the order they demonstrate the tasks.
The first rule is incredibly important. Frank goes first, then Gladys, then Frank and Gladys in either order. It looks like this:
On it’s own, that doesn’t tell us much. But the second rule says that Frank can’t go in 1 or 6. So Frank can only go in second or third (for his first task.) If Frank goes in fourth, there’s no room for the two Gladys’ plus the other Frank.
We’ll get to the other rules after, but watch what happens if we put Frank in third.
There’s no other way to put it since Frank can’t go in 6. And that takes care of all the Franks and Gladys’. So only Leslie is left to go in spots one and two.
We’ll call this scenario 1, and come back to it later.
Scenario 2 isn’t as interesting. Putting Frank in 2 doesn’t let us figure much out. Though we do know Leslie goes first, because Gladys can’t go before Frank.
So Leslie always goes first, no matter what.
When doing a game, I might not figure out these ordering deductions the first time I look at the rules. That’s why I read them first and think about them briefly before drawing anything.
Look for rules that mention the same variable. These can be combined to make deductions.
Now that we have ordering figured out, let’s look at the other rules. They’re all about tasks.
Rules 3 and 4 tell us which tasks Gladys and Leslie can’t perform.
Both rules mention H. Since Gladys and Leslie can’t demonstrate H, only Frank is left. Frank must demonstrate H.
The next rule says that T must go right before M.
This TM rule produces interesting results in the first scenario. Leslie can’t demonstrate T, so only Frank or Gladys can demonstrate T.
Except, M comes after T. And Gladys can’t demonstrate M. So Frank can’t demonstrate T, because then M would be with Gladys.
So it must be Gladys that demonstrates T, and Frank demonstrates M. GF demonstrates TM.
The second Frank must demonstrate M, because it’s the only Frank with a Gladys in front.
The first Frank therefore has to demonstrate harvesting (since no one else can demonstrate harvesting.)
That’s about all we can figure out. We know most things when Frank is in 3, but we don’t know very much when Frank is in 2. This game depends on knowing all the rules quite well.
It’s also important to note that W, S and P all have no rules.
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Amy says
Hi Graeme,
I had a problem with the rule #1. Can you please help explain how the first rule indicates F – G,G and F anywhere after the first G? (Instead of F – G,G – F ?)
I was able to see that the rule indicates this as I was attacking #8, but it would have been nicer if I was able to see this firsthand!
Thank you so much for your help.