PT14.S2.Q25- A letter submitted to the editor of a national

Comments

• 1 Like

  qs2159 Member

  November 2020 edited November 2020 342 karma

  So I think what's the flaw in E is that Emily fails to consider the chance of the flying animal between trees could be a mammal, which is similar to the editor's error.
• 1 Like

  canihazJD Alum Member Sage ⭐

  November 2020 edited November 2020 8313 karma

  Holy crap I thought this one was a smoker. Anyone else?

  A letter submitted to the editor of a national newsmagazine was written and signed by a Dr. Shirley Martin who, in the text of the letter, mentions being a professor at a major North American medical school. Knowing that fewer than 5% of the professors at such schools are women, the editor reasons that the chances are better than 19 to 1 that the letter was written by a man.

  ok so...

  <5% of professors are women
  Letter writer Dr. Shirley Martin mentions being a Professor
  So better than 19 to 1 chance the letter was written by a man.

  Flaw 1: Just because 5% of professors at all such schools are women, doesn't mean 5% at Dr. Shirley Martin's school are women. Maybe it's an all female faculty, in which case the odds are 0% its a man.

  Flaw 2: “mentions” being a professor isn't the same as being a professor. We don't know if Shirley is in this set or not... it's just suggested.

  Flaw 3: ignores that the name is SHIRLEY which affects odds of being a specific gender.

  Flaw 4: assumes that letter writing conforms to male/female ratio of professors

  A.
  19/20 computers are purchased for games (5% of computers are not for games) note: not less than
  First computer sold today wasn’t
  So, the next 19 will be for games

  Flaw: Overall average does not have to apply as a constant. Maybe the first 50 are sold for word processing and the next 950 are sold for games. Whole to part.

  This isn’t parallel. In the stimulus we have confirmation of inclusion in a set (is a professor) as justification for assuming the overall ratio applies. In this argument we have both confirmation of inclusion in the set (of computers) and the minority component of the ratio (non gaming). For this to match it should be:

  5% of computers sold not for games
  We sold a computer
  So 19:1 chance it was for games.

  Or the stimulus would have to say:

  19/20 professors are male
  This letter from a professor is from a female
  So the next 19 letters will be from a male.

  B.
  Fewer than 1 in 20 manuscripts submitted are accepted.
  Since only 15 were submitted last week there is almost no chance any of them will be accepted.

  Flaw is similar to A. Structure wrong… the 15 was enough to eliminate under time for me. Also under time I was like, A and B are too similar so they're likely both wrong.

  On BR I’ll say the structure if corrected would be:

  Fewer than 1 in 20 manuscripts submitted are accepted.
  This manuscript was submitted.
  So it has a 19 to 1 chance of not being accepted.

  Both A and B are compelling if you honed in on the whole-to-part...ness of the stimulus, but the structure is wrong for both, and if you are going solely on flaw similarity, I think they are both as similar to the stimulus, therefore both wrong.

  C.
  Less than 5% of last year's graduating class took latin.
  Howard took latin.
  So if he graduated last year, it is likely that one of the other latin scholars would not have graduated.

  This just… makes no sense. Maybe they’re trying to get you to think there’s only 20 graduates? We don't know enough… why can't all of the latin scholars have graduated? Who said all the latin scholars took latin last year? Not worth the thought under time… eliminate and move.

  D.
  More than 95% of the planes built last year met gov standards for large airliners.
  Since small planes account for just under 5% of planes built last year
  All their large planes met gov standards.

  Wrong flaw. Assumes no overlap. Why can’t couldn’t small planes have met gov standards for large airliners? Eliminate.

  E.
  More than 19/20 animals in preserve are mammals (more than 95% are mammals)
  Less than 1/20 are birds (less than 5% are birds)
  Greater than 95% chance the animal Emily saw flying between two trees in the refuge was a mammal.

  Why does the ratio in the preserve have to transfer to the ratio in the refuge? Similar to flaw 1 but not exact.

  But more importantly: the fact that this thing was freakin' FLYING affects the odds that it is a bird, just like being named Shirley affects the odds that you are a woman. This is the answer.

  Target flaw: fails to consider relevant information.

  Note that the use of ratios, percentages, etc. was one big distractor element. None of it contributed to an answer being correct or incorrect. I hate math so screw you LSAC.
• 2 Likes

  LOWERCASE EVERYTHING Member ⭐

  November 2020 edited November 2020 1952 karma

  i think the flaw is that the author failed to note other relevant data that were given, and made a conclusion solely on general stats.

  stimulus: author failed to consider the likelihood of men named "shirley"

  answer choice e: author failed to consider the likelihood of a flying mammal

  here's a similar argument that i made up:

  "since more than 95% of the living creatures live under the sea, and less than 5% live on land, there is a greater than 95% chance that the creature i played tennis with yesterday live under the sea."

  flaw: i failed to consider the likelihood of a tennis-playing creature that live under the sea.

  hope this helps!
• miriaml7 Live Member

  November 2020 1016 karma

  I have the exact same feelings towards math lol As always, thank you for your incredible explanation!! @canihazJD Thank you!! @qs2159 @"LOWERCASE EVERYTHING"