Question of the Day (April 10)

Quant

If $x$ and $y$ are positive integers, is $x^{16} - y^8 + 345y^2$ divisible by 15?

(1) $x$ is a multiple of 25, and $y$ is a multiple of 20

(2) $y = x^2$

Correct Answer - B - (click and drag your mouse to see the answer)

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Verbal

Many people suffer an allergic reaction to certain sulfites, including those that are commonly added to wine as preservatives. However, since there are several winemakers who add sulfites to none of the wines they produce, people who would like to drink wine but are allergic to sulfites can drink wines produced by these winemakers without risking an allergic reaction to sulfites.

Which of the following is an assumption on which the argument depends?

(A) These winemakers have been able to duplicate the preservative effect produced by adding sulfites by means that do not involve adding any potentially allergenic substances to their wine.
(B) Not all forms of sulfite are equally likely to produce the allergic reaction.
(C) Wine is the only beverage to which sulfites are commonly added.
(D) Apart from sulfites, there are no substances commonly present in wine that give rise to an allergic reaction.
(E) Sulfites are not naturally present in the wines produced by these winemakers in amounts large enough to produce an allergic reaction in someone who drinks these wines.

Question Discussion & Explanation

Correct Answer - E - (click and drag your mouse to see the answer)