Logical Reasoning

PT124 · S1 · Q13 Some doctors believe that a certain

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Some doctors believe that a certain drug reduces the duration of episodes of vertigo, claiming that the average duration of vertigo for people who suffer from it has decreased since the drug was introduced.

Evidence

During a recent three-month shortage ~CD of the drug, there was no significant change in the average duration of vertigo.

Conclusion

We can conclude that the drug has no ~E effect on the duration of vertigo.

Evaluate

The argument assumes that if during a ~CD → ~E three-month shortage of the drug, there was no significant change in the average duration of vertigo, then the drug has no effect on the duration of vertigo.

13.

Which one of the following is an assumption required by the argument?

  1. Correct

    If a drug made a

    Why this is right

    This restates the assumption E → CD in contrapositive form.

    Skill tested: Necessary Assumption · how this choice captures the argument's function is the move to repeat next time.

    80% picked this

  2. If there were any change

    Negated Logic

    This restates the assumption CD → E in a clever form of a contrapositive.

    5% picked this

  3. A period of time greater

    Too Strong

    Even if a period of time greater than three months would have been better to use, three months could still be enough time to make the determination satisfactorily.

    11% picked this

  4. Changes in diet and smoking

    Weakens

    This makes it more likely that any change in the average duration of vertigo since the introduction of the drug is the result of the drug.

    2% picked this

  5. There are various significant factors

    Too Strong

    There need not be various significant factors other than the drug that could explain the decrease in the average duration of vertigo since the drug was introduced. One factor would be enough. Furthermore, it’s unknown whether the doctors who believe there has been a reduction in the average duration of vertigo are correct that such a reduction has occurred.

    2% picked this

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