Q17 - Any food that is not

[tamwaiman]

I want to check my reasoning why (E) is incorrect.
Since what the first sentence of the argument mentions is disease-causing bacteria , if (E) replaces bacteria with disease-causing bacteria, it would be correct.

[ManhattanPrepLSAT1]

Hmmm. I don't see it. Where do you see it possible to infer that if a food contains no [disease-causing] bacteria, then it has been preserved by an acceptable method? According the statements given, we know some things about acceptable methods but we cannot say that only acceptable methods do not have disease-causing bacteria. It could be possible that some foods are never preserved and simply never had disease-causing bacteria.

For others looking for help on this one...

We need to find the answer choice that must be true based on the given statements. It's nearly impossible to predict the answer choice after reading the stimulus, so it'll be easiest to compare the answer choices to the given information, looking for slight shifts or misdirections in the information.

(A) is contradicted by the information. in fact we learn that some foods preserved by an acceptable method may have disease-causing bacteria.
(B) is unsupported. We know that some preservation methods destroy natural food enzymes that cause food to spoil, but we do not know that that do not sterilize food. And even if we grant that destroying those enzymes did sterilize food, the answer choice would still be too strong; since we only know this to be true of some preservation methods.
(C) is unsupported. The rate of discoloration is not discussed.
(E) is the reverse of answer choice (A) and is unsupported. We simply do not know that only foods that have been preserved by an acceptable method have no bacteria. There may be some foods that occur naturally without bacteria.

That leaves us with answer choice (D) as the correct answer and paraphrases the first sentence.

Hope that helps, but let me know if you have further questions on this one!

[Michelle5]

Would someone be able to show the symbolism in this problem? I got

~Sterilized and ~Sealed --> Bacteria
~Bacteria --> S or S

This is why I got "D" as correct from the contrapositive.

Thank you!!

[timmydoeslsat]

I would show it a little differently.

~[ST and SE ] ---> Can contain BAC

[ST and SE ] ---> ~BAC


The idea of saying not A and B = ~[A and B]

We know that if you do not have both ST and SE....bad things happen.

Whether it be the case that only one of the two occurs or if it is the case that neither occurs, that necessary condition is going to be triggered.

So with answer choice (D), we know we have ~STE, which means that we are going to have a situation of ~[STE and SE]. And this means it can contain BAC. We know that we will have a situation occur where both occur, as we know STE is not occuring.

[jamiejames]

I would show it a little differently.

~[ST and SE ] ---> Can contain BAC

[ST and SE ] ---> ~BAC


The idea of saying not A and B = ~[A and B]

We know that if you do not have both ST and SE....bad things happen.

Whether it be the case that only one of the two occurs or if it is the case that neither occurs, that necessary condition is going to be triggered.

So with answer choice (D), we know we have ~STE, which means that we are going to have a situation of ~[STE and SE]. And this means it can contain BAC. We know that we will have a situation occur where both occur, as we know STE is not occuring.

So it's just the contra of the first part?

[timmydoeslsat]

I would show it a little differently.

~[ST and SE ] ---> Can contain BAC

[ST and SE ] ---> ~BAC


The idea of saying not A and B = ~[A and B]

We know that if you do not have both ST and SE....bad things happen.

Whether it be the case that only one of the two occurs or if it is the case that neither occurs, that necessary condition is going to be triggered.

So with answer choice (D), we know we have ~STE, which means that we are going to have a situation of ~[STE and SE]. And this means it can contain BAC. We know that we will have a situation occur where both occur, as we know STE is not occuring.

So it's just the contra of the first part?

It is really just giving us that sufficient condition we want. We know that the sufficient condition of ~[ST and SE] will be fulfilled.

[monygg85]

I have a question,

Doesnt the stimulus need to say ~Sealed also for the condition ~Sterilized & ~Sealed to be triggered?

I was confused on this problem bc D says ~Sterilized but I was under the impression that I needed ~Sealed to come to the conclusion that Disease Causing Bacteria will be there.

Im confused by this..

[sumukh09]

I have a question,

Doesnt the stimulus need to say ~Sealed also for the condition ~Sterilized & ~Sealed to be triggered?

I was confused on this problem bc D says ~Sterilized but I was under the impression that I needed ~Sealed to come to the conclusion that Disease Causing Bacteria will be there.

Im confused by this..

The stim never says that disease causing bacteria "will" be there if both conditions (~sterilized + ~sealed) are met; it only says there can be disease causing bacteria which is a lot less stronger than saying it will be there. For D), we don't need ~sealed, because it's already given to us. We know a preservation technique has been used, and we know that preservation technique does not involve sterilization + sealed, since D tells us the food is non sterilized, so it must be that the growth of bacteria has been slowed. Since the second of the two preservation techniques has been used, we also know the food has not been sealed. It is an either or scenario as illustrated below:

If Sterilized + Sealed ---> ~Slowed; if Slowed ---> ~Sterlized + ~Sealed

[timsportschuetz]

The key to solving this question is this: Conditional logic CANNOT be diagrammed if words such as "can, may, could, might" are present. If you encounter such words, NO conditional logic is present!

Therefore, the only conditional statement in this question is:
Sterilized & properly sealed --> No Bacteria

A possible correct answer could state: If Bacteria present, then not properly sterilized or not properly sealed. However, this answer was not one of the choices.

You have to be VERY careful when considering if conditional logic is actually present. The more recent LSAT's have made more and more use of this technique to trip up test takers. I hope this helps a little.

[Dkrajewski30]

Maybe this explanation I did for myself can help others.

A. All food is preserved by an acceptable method is free of disease-causing bacteria.
Not necessarily true. All we know for sure is that acceptable method >>>>> at least slows the growth, given the 2nd to last sentence. If we knew all acceptable methods were sterilized and sealed, then A would have to be true, since sterilized and sealed >>>>> no bacteria, given the 2nd sentence. But we don't know that since we can't rule out acceptable methods that don't sterilize and seal.

B. Preservation methods that destroy enzymes that cause food to spoil do not sterilize the food.
Not enough information to support this. It goes logically too far since for all we know, these methods do sterilize the food. Only the last sentence speaks to these methods, and it says nothing about whether they sterilize.

C. Food preserved by a sterilization method is less likely to discolor quickly than food preserved with other methods.
Wrong for the same reason as B. It isn't supported since the last sentence offers little information about these methods.

D. Any nonsterilized food preserved by an acceptable method can contain disease-causing bacteria.
We know sterilized and sealed >>>> no bacteria. But this food in question hasn't been sterilized, and given the first sentence of the text, we know for certain that if a food is not sterilized and sealed, then it can contain bacteria. You might say 'what if it's sealed'? Either way, we know for sure the food hasn't been sterilized, and so this food in question is NOT sterilized AND sealed. At best, it's only sealed. Given that, we know it fits the conditional statement in the first sentence. And since it does, it has to be true that it can contain bacteria.

E. If a food contains no bacteria, then it has been preserved by an acceptable method.
Just not supported. We don't even know acceptable method >>>> no bacteria, forget the no bacteria >>>> acceptable method statement. For all we know, there are other ways to get rid of bacteria other than food-preservation techniques, which is what we consider these acceptable methods to be. Alternatively, if a food has no bacteria, then perhaps it didn't have any in the first place, and we didn't need to do anything to get rid of it. That food hasn't been preserved by an acceptable method. Now, we know in this case given the first sentence that it could contain bacteria, since any food not sterilized and sealed can contain it. But it's consistent with the text to say a food can have no bacteria and not be preserved. It's even consistent to say an unacceptable method can get rid of the bacteria - maybe someone does something stupid but it gets rid of the bacteria.

[krisk743]

I didn't like C because of quickly...but I still chose that when between C and D.

I know D is a def. MBT, but C seemed to "combine" ideas about the food coloring enzyme more and I thought it MAY have been that.


Is combining for ideas mainly for MSS and shouldn't worry about it on MBT? My spidey senses tingled on the word quick but idk why I still chose it. I suffer from that a lot