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Sajjad1994
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Computer programs exist that attempt to generate random numbers, but n 09 May 2025, 00:27
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C
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Computer programs exist that attempt to generate random numbers, but no such program can fully replicate a truly random selection. Computer programs are, by definition, a set of instructions that use an input to generate an output. If both the input and the algorithm are known, the result is fully predictable. Even the best random number generation programs can only be called pseudo-random because the input itself is generated by the program. As a result, a pattern will emerge within the results, even if the program is sophisticated enough to make the pattern very complicated, and that pattern can be used to predict future results. True random number generation often depends on measurement of an unpredictable physical phenomenon, such as weather patterns or atmospheric radiation, and using that measurement as an input to generate a result.
The passage provides information sufficient to infer each of the following statements EXCEPT:

A. The outputs of random number generators that provide their own input could, with enough information about past results, eventually be predicted.
B. If a person knew both the algorithm that a corporation used to generate a truly random number and the atmospheric measurements that served as the input, the person would be able to generate the same output obtained by the corporation.
C. With a sufficiently large table of the results of a pseudo-random number generator over time, it would be possible to derive the input and algorithm used to generate those results.
D. The integrity of applications for which the unpredictability of the result is vital, such as lotteries or data encryption, can be best preserved by using a method of random number generation that is truly random.
E. It is impossible to know the exact amount of atmospheric radiation emitted at a particular location and time until after a measurement is taken.

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C
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Vissamsetty
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Computer programs exist that attempt to generate random numbers, but n 14 May 2025, 08:50
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Bro need explanation on this - My answer is B:

Why B - As mentioned in the passage using the atmospheric measurements, we can generate random numbers. It can be inferred that even though the corp and person uses the same algo with atmosphere as input should result in different results as the number is random.

why not C - If a large table of results can be displayed and with very complex pattern we can still figure out the input and algo with it. (it is written in the para not my mind lol).

So what's the answer and why is C the correct answer??
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Computer programs exist that attempt to generate random numbers, but n 17 May 2025, 06:17
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OE

The four wrong answers to this Inference EXCEPT question are statements that must be true according to the information provided by the passage. The correct answer, therefore, is something that cannot be deduced using the information provided. This is (C). While the passage does say that knowing the input and algorithm allows one to fully determine the results of a random number generator, and that pseudo-random programs produce results that have patterns that are ultimately predictable, this only means that it is possible to determine future results. It does not necessarily mean that it is possible to reverse-engineer the initial input and algorithm from the results.

(A) is supported by combining the given definition of pseudo-randomness (“the input itself is generated by the program”) and the idea that pseudorandomness produces patterns that are predictable. Likewise, (D) must be true, since a pseudo-random number generator is predictable, whereas a truly random program is not.

The passage describes atmospheric radiation as “unpredictable,” making it a good source for true randomness, so (E) is true and can be eliminated. On the other hand, if someone obtained the measurements after they were taken and knew the algorithm being used to generate the random number, they would be able to generate the same result obtained by the original program since true-random number generation depends on the input being unpredictable, not the algorithm. As a result, (B) is also true.

Answer: C