The only preexisting recordings that are transferred onto compact disc are those that record companies believe will s...

Naz on May 27, 2015

This is a strengthen with sufficient premise question. Remember that a sufficient premise is sufficient for a conclusion, if and only if the existence of the premise guarantees or brings about the existence of the conclusion. Therefore, we need to find the premise that 100% guarantees the conclusion. The way you want to attack these answer choices is two-pronged. Ask yourself, does it strengthen? If it doesn't, then cross it out and continue to the next answer choice. If it does strengthen, however, then ask yourself whether or not the premise guarantees the conclusion.

Conclusion: "most classic jazz recordings will not be transferred onto compact disc."

Why? "The only preexisting recordings that are transferred onto compact disc are those that record companies believe will sell well enough on compact disc to be profitable." And we are told that few classic jazz recording are played on the radio.

So, the first thing that should jump out at you is the portion about the radio. We have never been given any info about the radio, and yet we are using it as support for our conclusion. This means that our correct answer will most likely have to connect this piece of disjointed evidence for us.

So if a preexisting recording is transferred onto compact disc, then those record companies believe it will sell well enough on compact disc to be profitable.

P1: TCD ==> BP
not BP ==> not TCD

"few classic jazz recordings are played on the radio."

Remember that "few" equates to "some."

Q1: CJR-some-PR
PR-some-CJR

Now, what this essentially means is that since only some classic jazz recordings are played on the radio, the rest of them--i.e., most of them--are not played on the radio.

CJR-most-not PR
not PR-some-CJR

"So, most classic jazz recordings will not be transferred onto compact disc."

C: CJR-most-not TCD
not TCD-some-CJR

Let's look at answer choice (C): "The only recordings that are played on the radio are ones that record companies believe can be profitably sold as compact discs."

(C): PR ==> BP
not BP ==> not PR

Does this answer choice strengthen the argument? No.

Answer choice (C) does nothing to strengthen the relationship between the premise and the conclusion. We can combine Q1 and (C) like so: CJR-some-PR ==> BP to conclude: CJR-some-BP, i.e. few classic jazz recordings are ones that record companies believe can be profitably sold as compact discs. This however, get's us nowhere. Knowing that record companies believe recordings will sell well enough on compact disc to be profitable is a necessary condition, which we know leads us to no other information. Thus, answer choice (C) does not strengthen the argument.

Let's look at answer choice (E): "No recording that is not played on the radio is one that record companies believe would be profitable if transferred to compact disc."

So this is a little tricky, but essentially we are saying "No not A is B." We know in a simple "No A is B," we diagram it: A ==> not B. Thus, in this situation we will diagram it: Not A is not B.

(E) not PR ==> not BP
BP ==> PR

Does this answer choice strengthen? Yes.

We can connect the inference we made from Q1 to (E) like so: CJR-most-not PR ==> not BP to conclude: CJR-most-not BP, which we can connect to the contrapositive of P1 like so: CJR-most-not BP ==> not TCD to conclude: CJR-most-not TCD, i.e. the conclusion of the argument.

Therefore, answer choice (E) helps strengthen the argument.

Now, does the premise guarantee the conclusion? Yes.

As we discussed above, answer choice (E) helps us create the chain: CJR-most-not PR ==> not BP, which leads us to CJR-most-not BP, which can then connect like so: CJR-most-notBP ==> not TCD to conclude: CJR-most-not TCD.

Thus, as you can see, answer choice (E) both strengthens the argument and guarantees the conclusion.

Hope that clears things up! Please let us know if you have any other questions.

Bluebell7612 on July 11, 2019

How could it be that "some played on radio" = "most not played on radio" when some could be at least one or all?

Ravi on July 11, 2019

@Bluebell7612,

Happy to help. This is a tricky question. You're right that "some"
means at least one and can include all. However, we know that most of
the jazz recordings aren't played on radio because it's implied based
on the context of the sentence, as we know that most jazz recordings
will not be transferred onto compact disc. The only way for this to
make any sense is if most jazz recordings are not played on the radio.
We can therefore infer that "few classic jazz recordings are played on
the radio" actually means that most jazz recordings aren't played on
the radio.

Does that make sense? Let us know if you have any other questions!