#17 - Local, Could Be True

[Dave Killoran]

Complete Question Explanation
(The complete setup for this game can be found here: lsat/viewtopic.php?f=357&t=12842)

The correct answer choice is (E)

The conditions in the question stem produce the following initial diagram:

G3-Q17-d1.png

From the first rule, then, we can infer that the third and sixth beads must be R:

G3-Q17-d2.png

From the second and third rules, the seventh bead cannot be R or O:

G3-Q17-d3.png

The last rule stipulates that all five bead colors must be used in any section of eight beads, and thus far neither G nor O has been used in the first eight beads. Therefore, because the seventh bead cannot be O, it must be G, and the eighth bead must be O:

G3-Q17-d4.png

This information eliminates answer choices (A), (B), and (C). From the third rule, when the eighth bead is O, then the ninth bead cannot be R, which eliminates answer choice (D). Accordingly, answer choice (E) is correct.

Overall, this is a challenging question.

[LSAT2018]

For this question, I was left with answer choices (B) and (E).
Why can't answer (B) be true?

[Malila Robinson]

Hi LSAT 2018,
According to the rules you would end up with:
P-Y-R-P-Y-R-_-_-_
1-2-3-4-5-6-7-8-9
You need to get all the colors into any 8 bead strand so you need to add an Orange and Green. You can't put the Orange next to the Red so Orange has to be in the 8th spot with Green in the 7th.
Hope that helps!
-Malila

[clem]

Hi there, I also narrowed down to B and E and didn’t understand why E is correct. You can’t put orange next to red, but why couldn’t you have GGO in positions 7, 8, and 9? So it would be:

P-Y-R-P-Y-R-G-G-O
1-2-3-4-5-6-7-8-9

That satisfies the requirement that all colors are used, separates red and organge, and double beads are allowed as long as they’re green. Any help would be much appreciated!

[Jamena Pirone]

Hi clem,

The last rule states that there must be at least one bead of each color in any 8 consecutive beads. In the 9-bead strand you posited, there is no orange bead in the first 8 beads.

[clem]

AHA. That makes sense now — thank you for the help and the quick reply!

[shibascream]

How are we supposed to know that by saying "ANY portion of the strand containing 8 consecutive beads" LSAT is specifically referring to the first 8 beads? Couldn't the wording of that rule also allow the segment in question to be beads 2 through 9 since that is also technically a strand of 8 consecutive beads? That definitely confused me!

[Adam Tyson]

It DOES refer to beads 2 through 9, shibascream, and also to beads 3 through 10, 4 through 11, etc. ANY portion of 8 beads has to obey that rule, no matter which 8 consecutive beads in the strand we're looking at. That means that you need every color in the first 8 beads, and you also need every color in beads 2 through 9 in this question.

In our explanation you can see that no matter what color we put in the 9th position, all 5 colors will have been used in the 8-bead portion running from 2 through 9. But we have to make sure we get both green and orange into spaces 7 and 8, because otherwise we would have a string of 8 beads that did not include every color, violating that last rule.

If it helps, think of "any" as meaning the same thing as "every" in that rule. Every 8-bead portion must have all 5 colors in it, no matter where in the string of beads those 8 beads are situated.