CAT Critical Reasoning Practice question with Solution 86

We’ve got a tragic story: Theodore Cooper, designer of the Quebec Bridge, receives word that there’s danger on the construction site; he telegraphs immediately, but it’s too late, and 84 workers plunge to their death. They didn’t die completely in vain, though; as a result of their misfortune, the process of bridge construction was altered. Whereas engineering “rules of thumb” had been used in the past, they were now abandoned in favor of “rigorous applications of mathematical analysis.” (E) is inferable: Before the Quebec tragedy in 1907, bridge builders had been accustomed to relying on “engineering rules of thumb” (and thus relying on whatever level of mathematical analysis was incorporated in those rules); as the 1907 disaster showed, these rules didn’t ensure complete safety. That’s all (E) says.

(A) is too broad; the Quebec Bridge was unsafe at one period of its construction, but for all we know, plenty of pre-20th century bridges were completely safe for public use, despite their engineers’ reliance on non-rigorous “rules of thumb.”

(B) We’re never told that Cooper’s absence from the site led to the disaster; we don’t know that he would have made a difference if he had been on site. The stimulus blames the then customary lack of rigorous mathematical analysis for the disaster.

(C) We’re never told why 19th century engineers relied on rules of thumb. Maybe their analytical methods were inadequate. On the other hand, maybe it was a matter of timesaving or cost-cutting.

(D) is too strong; we don’t know that more rigorous application of mathematical analysis was the only thing that would have prevented the disaster. Maybe a wholly different bridge design, to take one example, could also have done the job.