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Difficulty:
35%
(medium)
Question Stats:
70% (01:22) correct
30%
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wrong
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Because of its simplicity and effectiveness, the Luhn algorithm dominates initial credit-card checks: if you mistype any single digit, it flags the error; if you swap two adjacent digits, it flags that too.
Which of the following is most strongly supported by the information above?
A) Any card number that passes the Luhn algorithm is a valid credit card number.
B) If a card number has a single mistyped digit, the Luhn algorithm will identify the error.
C) A number that fails the Luhn algorithm can still be a valid credit card number.
D) The Luhn algorithm detects all types of data-entry errors, including nonadjacent transpositions.
E) Because the Luhn algorithm is effective, other fraud-screening tools are unnecessary.
Which of the following is most strongly supported by the information above?
A) Any card number that passes the Luhn algorithm is a valid credit card number.
B) If a card number has a single mistyped digit, the Luhn algorithm will identify the error.
C) A number that fails the Luhn algorithm can still be a valid credit card number.
D) The Luhn algorithm detects all types of data-entry errors, including nonadjacent transpositions.
E) Because the Luhn algorithm is effective, other fraud-screening tools are unnecessary.
Updated on: 01 Sep 2025, 17:03
Originally posted by MartyMurray on 31 Aug 2025, 10:35.
Last edited by MartyMurray on 01 Sep 2025, 17:03, edited 1 time in total.
Last edited by MartyMurray on 01 Sep 2025, 17:03, edited 1 time in total.
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Because of its simplicity and effectiveness, the Luhn algorithm dominates initial credit-card checks: if you mistype any single digit, it flags the error; if you swap two adjacent digits, it flags that too.
Which of the following is most strongly supported by the information above?
This is a Conclusion question, and the correct answer will be the choice such that we can find clear support for it in the passage.
A) Any card number that passes the Luhn algorithm is a valid credit card number.
This is not supported by the passage.
The information in the passage indicates only that the Luhn algorithm detects errors when single digits are mistyped or adjacent digits are swapped.
It does not indicate how the algorithm works on indicate that any number that passes the Luhn algorithm is valid.
Given what the passage says, it could be that there are characteristics that could make a card number invalid other than the ones mentioned in the passage that the Luhn algorithm flags.
So, the facts in the passage do not indicate that any number that passes the algorithm is valid.
Eliminate.
B) If a card number has a single mistyped digit, the Luhn algorithm will identify the error.
This choice is interesting.
The passage says the following:
if you mistype any single digit, it flags the error
We can see that the fact that the algorithm flags any error involving any mistyped single digit means that "If a card number has a single mistyped digit, the Luhn algorithm will identify the error." After all, the algorithm must "identify the error" to "flag" it.
Keep.
C) A number that fails the Luhn algorithm can still be a valid credit card number.
This could be true, but the passage does not support it.
All the passage indicates is that the Luhn algorithm detects errors in card numbers.
The fact that it detects errors does not support the conclusion that a number that is flagged by the algorithm can be valid.
Eliminate.
D) The Luhn algorithm detects all types of data-entry errors, including nonadjacent transpositions.
The passage indicates only that the Luhn algorithm detects two types of errors, mistyped single digits and swapped adjacent digits.
So, what this choice says about "all types of data-entry errors, including nonadjacent transpositions" is not supported. After all, the fact that the algorithm detects two types of errors does not mean that it detects all types.
Eliminate.
E) Because the Luhn algorithm is effective, other fraud-screening tools are unnecessary.
The passage indicates only that the Luhn algorithm "dominates initial credit-card checks" and that it flags two types of errors.
That information does not indicate that "other fraud-screening tools are unnecessary."
After all, the facts presented do not mean that the Luhn algorithm detects all forms of fraud since there could be forms of fraud that do not involve the two types of errors that, according to the passage, the algorithm can detect.
Eliminate.
Correct answer: B
Which of the following is most strongly supported by the information above?
This is a Conclusion question, and the correct answer will be the choice such that we can find clear support for it in the passage.
A) Any card number that passes the Luhn algorithm is a valid credit card number.
This is not supported by the passage.
The information in the passage indicates only that the Luhn algorithm detects errors when single digits are mistyped or adjacent digits are swapped.
It does not indicate how the algorithm works on indicate that any number that passes the Luhn algorithm is valid.
Given what the passage says, it could be that there are characteristics that could make a card number invalid other than the ones mentioned in the passage that the Luhn algorithm flags.
So, the facts in the passage do not indicate that any number that passes the algorithm is valid.
Eliminate.
B) If a card number has a single mistyped digit, the Luhn algorithm will identify the error.
This choice is interesting.
The passage says the following:
if you mistype any single digit, it flags the error
We can see that the fact that the algorithm flags any error involving any mistyped single digit means that "If a card number has a single mistyped digit, the Luhn algorithm will identify the error." After all, the algorithm must "identify the error" to "flag" it.
Keep.
C) A number that fails the Luhn algorithm can still be a valid credit card number.
This could be true, but the passage does not support it.
All the passage indicates is that the Luhn algorithm detects errors in card numbers.
The fact that it detects errors does not support the conclusion that a number that is flagged by the algorithm can be valid.
Eliminate.
D) The Luhn algorithm detects all types of data-entry errors, including nonadjacent transpositions.
The passage indicates only that the Luhn algorithm detects two types of errors, mistyped single digits and swapped adjacent digits.
So, what this choice says about "all types of data-entry errors, including nonadjacent transpositions" is not supported. After all, the fact that the algorithm detects two types of errors does not mean that it detects all types.
Eliminate.
E) Because the Luhn algorithm is effective, other fraud-screening tools are unnecessary.
The passage indicates only that the Luhn algorithm "dominates initial credit-card checks" and that it flags two types of errors.
That information does not indicate that "other fraud-screening tools are unnecessary."
After all, the facts presented do not mean that the Luhn algorithm detects all forms of fraud since there could be forms of fraud that do not involve the two types of errors that, according to the passage, the algorithm can detect.
Eliminate.
Correct answer: B
31 Aug 2025, 23:07
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Thanks MartyMurray
I rejected option A on the basis of reasoning that there can be other checks as well later since the given info only talks about initial checks "the Luhn algorithm dominates initial credit-card checks". Is my reasoning correct?
I rejected option A on the basis of reasoning that there can be other checks as well later since the given info only talks about initial checks "the Luhn algorithm dominates initial credit-card checks". Is my reasoning correct?
MartyMurray
