PrepTest 155

This concludes that we shouldn't install a radiant floor cooling system. To draw that conclusion, the premise should indicate that this hotel is in a region with humid summers. This just says the hotel is "not newly constructed" and will "not be a luxury hotel." So this answer choice doesn't follow the rules, so it's incorrect.

Argument or Facts:
Facts

Question Type:
Must Be True

Stimulus Summary:
We should install radiant floor heating in Bonjour hotels if they have radiant floor cooling or if they're luxury hotels. But we shouldn't install radiant floor cooling systems in hotels where it'll be humid during the summer.

Strategy Overview:

1. Argument or facts in passage?
   1. If argument, identify premises and conclusions
2. Sufficient/necessary conditions in the passage?
   1. If so, diagram statements and draw any deductions
3. Use anticipation to find the answer choice that is absolutely, 100% true

Answer Anticipation:
Roughly half of all Must Be True questions are diagrammable. This question, which uses conditional keywords "if" and "any," is certainly among the half that are diagrammable. Recall that "if" and "any" both refer to sufficient conditions, and diagram this as:

1. Radiant Cooling or Luxury -> Radiant Heating
2. Humid Summer -> NOT Radiant Cooling

And we can take the contrapositives:

Contrapositive: NOT Radiant Heating -> NOT Radiant Cooling & NOT Luxury

Contrapositive: Radiant Cooling -> NOT Humid Summer

These cannot be combined, so we just have to find an answer choice that follows one or both of these rules.

Answer Choice Explanation:
This one follows all the rules. It first concludes that we should install a radiant floor heating system. To draw that conclusion, the premise should indicate that there's a radiant cooling system or that it's a luxury hotel. The premise states it's a luxury hotel, so that conclusion is valid. This argument also concludes that we shouldn't install a radiant floor cooling system. To draw that conclusion, the premise should indicate that this hotel is in a region with humid summers. The premise states there's high humidity throughout the year, so that conclusion is also valid. Everything follows the rules here, so this answer choice is correct.

Key Takeaway:
When you have a sufficient condition with an "or" in it, either of the two halves is sufficient on its own to produce the necessary condition. For example, if your diagram reads "Orange Extract or Vanilla Extract -> Delicious Cake," you can determine that any cake using orange extract is delicious, and any cake made with vanilla extract is delicious.

This concludes that we shouldn't install a radiant floor cooling system. To draw that conclusion, the premise should indicate that this hotel is in a region with humid summers. The premises only indicate that the property is not a luxury hotel and it has a radiant floor heating system. This answer choice doesn't follow the rules, so it's incorrect.

This concludes that we shouldn't install a radiant floor heating system. However, we don't have a principle that could justify that conclusion. The principle will only allow us to conclude when we should install a radiant floor heating system. (We can only draw conclusions about necessary conditions, and "should install a radiant floor heating system" is the necessary condition of the first premise.) That's enough to eliminate (D), even though it does validly conclude that we should not install a radiant floor cooling system because the region has humid summers.

This concludes that we should install a radiant floor cooling system. However, we don't have a principle that could justify that conclusion. The principle will only allow us to conclude when we shouldn't install a radiant floor cooling system. (We can only draw conclusions about necessary conditions, and "should not install a radiant floor heating system" is the necessary condition of the second premise.) That's enough to eliminate (E), even if it validly concludes that we should install a radiant floor heating system because the property is a luxury hotel.