In the first decade following the founding of the British labour party

Question

In the first decade following the founding of the British labour party, the number of people regularly voting for Labour increased five-fold. The number of committed Labour voters increased a further five-fold during the party’s second decade. Since the increase was thus the same in the first as in the second decade, the often-made claim that the Labour party gained more voters in the party’s second decade than in its ﬁrst is clearly false.

The reasoning in the argument is ﬂawed because the Argument

A. fails to specify dates necessary to evaluate the truth of the conclusion, even though the argument depends on distinguishing between two time periods

B. draws a conclusion that cannot be true if all the data advanced in its support are true

C. relies on statistical evidence that, strictly speaking, is irrelevant to establishing the conclusion drawn

D. fails to allow for the possibility that the policy positions advocated by the Labour party changed during the period in question

E. overlooks the possibility that more elections were held in one of the two decades than were held in the other

chetan2u · Answer

Hi..
 The argument talks of 5-fold increase in each decade..
but the 5-fold increase in the second decade is over a larger number. so conclusion is not correct

say initially 100 guys.. end of decade 500.. increase 500-100=400
then starting of new decade 500.. end of that decade 5*500=2500... increase 2500-500=2000..

clearly 2nd decade increase was more

B

Guest96 · Answer

In case it helps anyone, E is wrong because it talks about how many elections happened, but the argument is really about how much the number of Labour voters increased, not how often they voted. It's like saying you grew the same amount each year, and it doesn't matter how many times you were measured.

laborumplaceat · Answer

if initially the number of voters were x
after the first decade they increased to 5x (5 times)
so, increase was: 5x-x = 4x

in the second decade they increased to 25x (5 times 5x)
so, increase was: 25x-5x = 20x

so, increase in the second decade was indeed more than the increase in the first decade
so,  B

Sajjad1994 · Answer

Explanation

In first decade:  Labour voters increased five-fold, it mean if initial number was x, after first decade voters = 5x.
 In second decade:  increased five-fold again from 5x, it means after second decade voters= 25x.

Increase in first decade: 5x−x=4x new voters.
Increase in second decade: 25x−5x=20x new voters.

So the increase in voters in second decade is actually five times larger than in the first decade. But the argument says because the fold increase was same (five-fold), the claim that Labour gained more voters in second decade is false. This is wrong: the fold increase being equal doesn’t mean the absolute increase in voters is equal, if the base is larger, five-fold growth yields a much bigger absolute increase.

So the flaw is that the argument talks about fold increase being equal, then concludes number of new voters wasn’t greater in the second decade. But from the data given, the number of new voters was in fact greater in the second decade.

A.  Not really about specifying dates; dates are not the flaw here.

B.  Yes: the conclusion says the claim  “more voters in second decade than first”  is false. But if the data given are true, then 20x (second decade) vs 4x (first) means more voters in second decade, so conclusion cannot be true if data are true.

C.  It doe not use irrelevant stats; the stats directly show the opposite.

D.  Policy positions irrelevant to this mathematical point.

E.  Number of elections is irrelevant; they are talking about number of voters, not election frequency.

Answer: B

In the first decade following the founding of the British labour party

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In the first decade following the founding of the British labour party

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615 to 715 in 15 Days (Ria's Strategies)

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