#23- At Southgate Mall, mattresses are sold only at Mattress

[Desperatenconfused]

I don’t really understand the difference between C and D. Because the stimulus said that at the mall mattresses sold are only at Mattress Madness, I thought it was parallel to the only food in Diane’s apartment is in her fridge, rather than all the food in the apartment is in the fridge. Can anyone explain this difference to me?

[Desperatenconfused]

I don’t really understand the difference between C and D. Because the stimulus said that at the mall mattresses sold are only at Mattress Madness, I thought it was parallel to the only food in Diane’s apartment is in her fridge, rather than all the food in the apartment is in the fridge. Can anyone explain this difference to me?

I realize it’s the last sentence for both answers that are different that makes C more parallel than D. However, can someone confirm there is/isnt a difference in the first sentence (only = all?)

[Luke Haqq]

Hi Desparatenconfused!

In the stimulus, we have the following reasoning:

Mattress @ Southgate Mall Mattress Madness 20 percent off

That is, if it is a mattress being sold at Southgate Mall, then it is being sold at Mattress Madness, in which case it is 20% off. We can infer that if it is a Mattress being sold at Southgate Mall, then it is 20% off.

Answer choice (C) parallels this reasoning:

Food @ Diane's apartment Refrigerator Purchased within past week

That is, if something is food within Diane's apartment, then it is in the refrigerator, in which case it was purchased within the past week. We can infer that if it is food within Diane's apartment, then it was purchased within the past week. This has the same structure as the stimulus.

Answer choice (D) would be diagrammed as follows:

Food @ Diane's apartment Refrigerator Purchased within past week

So the structure would be identical. However, the problem is the conclusion reached in (D): "Therefore, all the food she purchased within the past week is in her apartment." This doesn't necessarily follow from the diagram. Based on the diagram, we know that if it's food in her apartment, then it was purchased within the past week. But it's possible that she also purchased food in the past week that isn't in her apartment (e.g., perhaps she went out to eat).

[Capetowner]

Hi Desparatenconfused!

In the stimulus, we have the following reasoning:

Mattress @ Southgate Mall Mattress Madness 20 percent off

That is, if it is a mattress being sold at Southgate Mall, then it is being sold at Mattress Madness, in which case it is 20% off. We can infer that if it is a Mattress being sold at Southgate Mall, then it is 20% off.

Answer choice (C) parallels this reasoning:

Food @ Diane's apartment Refrigerator Purchased within past week

That is, if something is food within Diane's apartment, then it is in the refrigerator, in which case it was purchased within the past week. We can infer that if it is food within Diane's apartment, then it was purchased within the past week. This has the same structure as the stimulus.

Answer choice (D) would be diagrammed as follows:

Food @ Diane's apartment Refrigerator Purchased within past week

So the structure would be identical. However, the problem is the conclusion reached in (D): "Therefore, all the food she purchased within the past week is in her apartment." This doesn't necessarily follow from the diagram. Based on the diagram, we know that if it's food in her apartment, then it was purchased within the past week. But it's possible that she also purchased food in the past week that isn't in her apartment (e.g., perhaps she went out to eat).

Why is the second link so specific if "Mattress Madness" could entail other things, perhaps pillows or racks or something? It seems some conditionals in this test take liberties in the way they expect us to interpret them. Logically, "mattress madness" would not be linkable here

[Jeff Wren]

Hi Capetowner,

It's important to realize that whenever we (and you) diagram conditional statements, the symbols that we use are simply shorthand for whatever the exact wording is used in the actual LSAT stimulus or answer choice. We do this to save time, but it's important to always return to the exact wording in the stimulus/answer choices to make sure that it is correct because sometimes a single wrong word can make an answer incorrect or the argument invalid.

Here, the stimulus uses the words "every mattress at Mattress Madness," so the term "Mattress Madness" used in the diagram specifically refers to "mattress at Mattress Madness" rather than anything else sold at Mattress Madness. Personally, if I were diagramming this on scratch paper under timed conditions, I'd probably just use the letters "MM" to represent this term in order to save time, since that is enough for me to know which term in the argument the letters refers to, but it makes more sense to write out the words in the forum for extra clarity.

However, even if the stimulus had said "everything sold at Mattress Madness is on sale at a 20% discount" (including other items besides mattresses), this would still be a valid argument using conditional reasoning. Since we know that every mattress sold at Southgate Mall is sold at Mattress Madness, if everything sold at Mattress Madness is on sale at a 20% discount (including mattresses), that would still prove our conclusion.