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Student: The majority of the 50 students in our class answered at leas
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22 Apr 2017, 06:50
Question Stats:
54% (01:41) correct 46% (01:51) wrong based on 273 sessions
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Student: The majority of the 50 students in our class answered at least 80% of the questions correctly on last year’s Algebra I final exam. If these final exam scores do accurately measure a student’s level of understanding, Marc must have learned less about algebra last year than most other students in our class, because he answered only 75% of the questions correctly on last year’s Algebra I final exam. Which of the following, if true, most seriously weakens the student’s argument? (A) Seven students answered less than 75% of the questions correctly on the final exam in Algebra I last year. (B) Marc is one of four students in the class who did not take an introductory  level algebra course offered by the school two years ago. (C) Marc is one of three students who answered exactly 75% of the questions correctly on the final exam in Algebra I last year. (D) The teacher estimated that last year’s ninthgrade Algebra I final exam was roughly twice as difficult as this year’s Algebra I final exam. (E) Only three students spent less time than Marc spent answering the questions on last year’s Algebra I final exam. Source : PowerScore
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Student: The majority of the 50 students in our class answered at leas
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Updated on: 04 Jun 2017, 20:58
As Marc did not take an introductory  level algebra course, he could not understand the Algebra1, that's why he learned less than other students of the class learned. I do not understand how it could be a weakener.
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Hasan Mahmud
Originally posted by Mahmud6 on 29 Apr 2017, 21:00.
Last edited by Mahmud6 on 04 Jun 2017, 20:58, edited 1 time in total.



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Re: Student: The majority of the 50 students in our class answered at leas
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30 Apr 2017, 02:21
IMO B But OA is difficult to digest. Please provide official explanation.
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Re: Student: The majority of the 50 students in our class answered at leas
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01 May 2017, 06:22
Good Question. The argument is saying the majority answered atleast 80% of the questions correctly last year. Then it is saying Marc Must have learned less algebra last year as he got only 75%. ( we are considering more marks = more understanding). The important words to note here are "learned less algebra last year" We need to weaken it. (A) Seven students answered less than 75% of the questions correctly on the final exam in Algebra I last year. Irrelevant. No where it is telling us relationship we require.(B) Marc is one of four students in the class who did not take an introductory  level algebra course offered by the school two years ago. Yes, It was not LAST YEAR but 2 years ago. Hence, conclusion is weakened.(C) Marc is one of three students who answered exactly 75% of the questions correctly on the final exam in Algebra I last year. Same as A.(D) The teacher estimated that last year’s ninthgrade Algebra I final exam was roughly twice as difficult as this year’s Algebra I final exam. Same as A.(E) Only three students spent less time than Marc spent answering the questions on last year’s Algebra I final exam. Same as A.
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Student: The majority of the 50 students in our class answered at leas
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01 Jul 2018, 11:36
official reply
The student argues that since more than half of the students in the class scored an 80% or better on the Algebra exam, and since Marc only scored a 75%, then Marc must have “learned less” about Algebra than most of the other students in the class. Unfortunately for the student, this requires a dangerous assumption: because Marc ended the year slightly behind most other students in terms of percentage score (75% to 80%), he must have made less progress during the year than most other students. In other words, the phrase “learned less” implies that someone makes less progress over time, and that may not necessarily be the case here.
Let’s consider an example:
Say you were to ask five people to train for a onemile race for two months. At the end of those two months, you time them as they run the mile and you record their results. Runners 1, 2, 3, and 4 each finish in exactly 6 minutes. Runner 5, however, takes 10 minutes to complete the race. Would it be fair to conclude that Runner 5 was the least improved runner over the course of those two months? Not necessarily. What if Runners 14 could already run a mile in 7 minutes prior to any training, whereas Runner 5 needed 30 minutes to run a mile two months ago? Now it seems clear that, while Runner 5 can still be described as the slowest runner in the group, saying that he or she is the least improved would be inaccurate. So the key when trying to gauge progress is to have a starting point to reference so you can truly measure how far someone has come. And the same is true of Marc in the stimulus. Certainly he was outscored on the exam by most of the students, but does that mean he learned less over the course of the year? We cannot conclude that unless we know where he started relative to everyone else. So to weaken this student’s claim that Marc learned less, we need an answer choice that suggests he made more progress (started further back) than the majority of his classmates.
Answer choice (A): This answer choice places Marc fairly low in the group of 50 students (only 7 of 50 scored worse than him), but this still does not impact the idea of how much he learned. Hence, this answer does not weaken the argument.
Answer choice (B): This is the correct answer. If Marc and three other students did not take the introductorylevel Algebra course, and the other 46 students all did, then it seems likely that Marc would have started the Algebra I class knowing less about the subject than his classmates. If that is the case then his final score of 75% could certainly represent much more learned (greater progress) over the course of the year than his classmates who scored 80% or better. Again, numbers can often make these ideas easier to grasp. Say that Marc, having missed the introductory course, began the year only knowing 10% about Algebra I and finished with a 75% (65% improvement). Most of his classmates however, having taken the introductory course, started the year at 50%. Even if they all finished at 90%, that’s still only a 40% improvement, which pales in comparison to Marc’s 65% increase. Clearly, even though Marc may not have finished in the tophalf of his class, he still could have learned more than those who outscored him.
Answer choice (C): This answer choice, like (A), only addresses where Marc finished relative to some of his classmates. Since we need an answer choice related to Marc’s progress over the course of the year, this answer cannot be correct.
Answer choice (D): The overall difficulty of the exam relative to other exams is completely irrelevant to Marc performance or his progress relative to his classmates.
Answer choice (E): The amount of time that Marc (or anyone else) spent answering questions is also irrelevant to how much he ultimately learned during the course relative to his classmates, so this answer is incorrect.



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Student: The majority of the 50 students in our class answered at leas
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17 Nov 2018, 23:26
hazelnut wrote: Student: The majority of the 50 students in our class answered at least 80% of the questions correctly on last year’s Algebra I final exam. If these final exam scores do accurately measure a student’s level of understanding, Marc must have learned less about algebra last year than most other students in our class, because he answered only 75% of the questions correctly on last year’s Algebra I final exam.
Which of the following, if true, most seriously weakens the student’s argument?
(A) Seven students answered less than 75% of the questions correctly on the final exam in Algebra I last year. (B) Marc is one of four students in the class who did not take an introductory  level algebra course offered by the school two years ago. (C) Marc is one of three students who answered exactly 75% of the questions correctly on the final exam in Algebra I last year. (D) The teacher estimated that last year’s ninthgrade Algebra I final exam was roughly twice as difficult as this year’s Algebra I final exam. (E) Only three students spent less time than Marc spent answering the questions on last year’s Algebra I final exam.
Source : PowerScore A Tag of Numbers and Percents should be added to this question.
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Student: The majority of the 50 students in our class answered at leas &nbs
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