#22- The folktale that claims that a rattlesnake’s age can

[mfs2021]

I want to be clear here: I have no issues with the question or the explanation to the correct answer of this question (E).

However, I think there is some carelessness in the explanations to the one of the wrong answer choices.

(A) is not sufficient to fully justify the conclusion.

"Rattlesnakes molt exactly once a year", when added to the premise "One new section is formed each time a rattlesnake molts" does not guarantee we can reliably determine a rattlesnake's age.

Nothing in the stimulus prohibits a new section from also being added to the rattle every time the rattlesnake sings "O Holy Night" in addition to when it molts.

If sections are an end product of molting amidst numerous other activities and events, and all sections are identical (nothing in the stimulus mentions distinguishing features from section to section) then a rattlesnake could have, say, 10 sections. But what of them? Who knows how many are from the rattlesnake's yearly molts, or from it's sunbathing routine? (A) gets to part of the equation (tying down the molting frequency). But the stimulus does not tie down the other part: sections being added to the rattlesnake, only going so far as to say that molting is sufficient to add one new section but nothing more.

We would need: 1) Rattlesnake molts exactly once a year + 2) A new section is formed every time the rattlesnake molts. + 3) Sections do not form on a rattlesnake unless the rattlesnake molts.

Then we could justify the numbers of sections bringing us to the rattlesnakes age. The stimulus does not provide #3, and thus A is not sufficient to justify the conclusion.

[Rachael Wilkenfeld]

Hi mfs,

I'm a bit confused by your response. We are not trying to justify the conclusion here. This is an assumption question, not a justify question. So we don't care if an answer choice by itself is sufficient to justify the conclusion. We only care that it's necessary for the conclusion to follow. For that, we would use the assumption negation technique and not the premise test that you use in your post.

If we were looking at answer choice (A) in a justify question, it would justify our conclusion. That's because if a rattlesnake molts EXACTLY once a year, it also doesn't molt additional times for additional reasons. It's exactly once, and we can then rely on the number of molts to equal (approximately) the number of years.

Please let me know if I've misunderstood your post, or if you have any other questions!

[Darchelle]

I still don't get why the answer is E.

[Jeff Wren]

Hi Darchelle,

First, if you haven't already done so, please read the earlier discussion in this forum thread, as several answers should be helpful.

There's been a lot already written on the forum for this question, including why Answer E is correct.

The discussion starts at the link below:

viewtopic.php?f=608&t=1851

I will only add that it's important to realize that this an Assumption question rather than a Justify question, and that you can use the Assumption Negation Technique to confirm that Answer E is correct.

If rattlesnakes molt at a different rate when food is scarce than when food is plentiful, then the number of moltings (which directly affect the number of rattle sections) would vary depending on these conditions. That would directly weaken the conclusion that the number of rattle sections would be a reliable indicator of the snake's age.

More information on Assumption questions, including the Assumption Negation Technique, can be found in "The Logical Reasoning Bible" or in the PowerScore LSAT courses.

[zebrowski]

However, our author need not assume that snakes molt exactly once a year, because it would also be okay if they molted twice a year, or once a month, or every 247 days, etc.

The discussion in this forum thread has been very very helpful. However, I still have some lingering doubts.

The author need not assume that snakes molt exactly once a year, but only that they molt at regular intervals. Granted. However, suppose snakes molted once every 10 years. Could we reliably determine a snake's age from the number of sections in its rattle? For my money, we could not. We could approximate a snake's age down to 10 years, but that is a far cry from a "reliable determination." So I think the author must assume that snakes molt at regular intervals not longer than a year or two.