#21 - During construction of the Quebec Bridge in 1907, the

[Adam Tyson]

It's implied in the combination of the last two statements of the stimulus, TZHUUMD22 - the rules of thumb had to be replaced by more rigorous math. The use of the comparative "more" in that last line indicates that the rules of thumb included at least some applications of mathematical analysis in order for the change to involve a "more rigorous" application. If the rules of thumb had no mathematical analysis at all, then the comparison would not make sense, and the author would have instead had to say "engineers would thereafter depend on rigorous applications of mathematical analysis."

And even if the rules of thumb had NO mathematical analyses, answer E would still be good! This is because whatever they did include, they were not sufficient to assure safety. Having zero math, if that is what they had, proved to be insufficient, as demonstrated by what happened with the Quebec bridge.

[TZHUUMD22]

Thank you for your detailed response Adam. I think LSAT usually makes the hard questions really word-sensitive. It is easy to ignore the implication of "more."

Thanks!

T

[teddykim100]

Hello,

just to double check my thought process I'd like to examine what Administrator wrote in the very first post of this thread regarding answer choice B

Admin wrote: "Answer choice (B) assumes that if Cooper had been at the bridge site, the cantilever would not have broken off. While this is possible, it is by no means certain. As a result, this choice is wrong."

answer choice B states "Cooper's absence at the bridge site resulted in the breaking of the cantilever"

Isn't Admin's stated assumption an illegal negation of answer choice B?

[Rachael Wilkenfeld]

Hi teddy,

I'm not sure why you would be doing negations at all in this question. It's a MBT question. We don't know if his absence caused the break or not. It seems like the measurement error caused the break. But in any case, we wouldn't want to negate the answer choice---this isn't an argument really, so there's no conclusion to analyze.

Unless we know for certain that it was the absence that caused the break, answer choice (B) will be incorrect.

Hope that helps!