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24 Aug 2025, 22:08
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Because of its simplicity and effectiveness, the Luhn algorithm is used for 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 detect the error.
C. Any card number that fails the Luhn algorithm must contain at least one data-entry error.
D. The Luhn algorithm detects all types of data-entry errors, including nonadjacent transpositions.
E. If a card number passes the Luhn algorithm, it must have been entered without any data-entry errors at all.
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 detect the error.
C. Any card number that fails the Luhn algorithm must contain at least one data-entry error.
D. The Luhn algorithm detects all types of data-entry errors, including nonadjacent transpositions.
E. If a card number passes the Luhn algorithm, it must have been entered without any data-entry errors at all.
24 Aug 2025, 22:08
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Official Solution:
Because of its simplicity and effectiveness, the Luhn algorithm is used for 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 detect the error.
C. Any card number that fails the Luhn algorithm must contain at least one data-entry error.
D. The Luhn algorithm detects all types of data-entry errors, including nonadjacent transpositions.
E. If a card number passes the Luhn algorithm, it must have been entered without any data-entry errors at all.
To answer a Most Strongly Supported question, stick to the literal claims in the stimulus. Only B is a direct, un-qualified restatement, so it is the single supported inference; every other option either adds new assumptions or stretches the given facts.
(A) Incorrect: The stimulus discusses the Luhn algorithm only as an initial check for data-entry mistakes; it never says that passing the check proves a number is an issued, valid credit-card account. This answer is going too far.
(B) Correct Answer: The passage states that the algorithm “detects any single-digit data-entry error,” which directly supports the statement that if a card number contains one mistyped digit, the algorithm will flag (detect) it.
(C) Incorrect: Although a number that fails the test might indeed be invalid, the text never asserts that failure rules out validity. Other factors (e.g., data corruption or a format mismatch) could cause a false failure, so the claim is not guaranteed.
(D) Incorrect: The passage mentions detection of adjacent digit swaps but says nothing about non-adjacent transpositions or “all types” of errors. This choice adds an unsupported generalization that's going outside of the scope of the premise and information given.
(E) Incorrect: Passing the Luhn check only eliminates the two specific error types listed (single-digit mistakes and adjacent swaps). Other entry errors, such as swapping non-adjacent digits or mistyping two digits could still slip through, making this statement too broad and not supported.
Answer: B
Because of its simplicity and effectiveness, the Luhn algorithm is used for 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 detect the error.
C. Any card number that fails the Luhn algorithm must contain at least one data-entry error.
D. The Luhn algorithm detects all types of data-entry errors, including nonadjacent transpositions.
E. If a card number passes the Luhn algorithm, it must have been entered without any data-entry errors at all.
To answer a Most Strongly Supported question, stick to the literal claims in the stimulus. Only B is a direct, un-qualified restatement, so it is the single supported inference; every other option either adds new assumptions or stretches the given facts.
(A) Incorrect: The stimulus discusses the Luhn algorithm only as an initial check for data-entry mistakes; it never says that passing the check proves a number is an issued, valid credit-card account. This answer is going too far.
(B) Correct Answer: The passage states that the algorithm “detects any single-digit data-entry error,” which directly supports the statement that if a card number contains one mistyped digit, the algorithm will flag (detect) it.
(C) Incorrect: Although a number that fails the test might indeed be invalid, the text never asserts that failure rules out validity. Other factors (e.g., data corruption or a format mismatch) could cause a false failure, so the claim is not guaranteed.
(D) Incorrect: The passage mentions detection of adjacent digit swaps but says nothing about non-adjacent transpositions or “all types” of errors. This choice adds an unsupported generalization that's going outside of the scope of the premise and information given.
(E) Incorrect: Passing the Luhn check only eliminates the two specific error types listed (single-digit mistakes and adjacent swaps). Other entry errors, such as swapping non-adjacent digits or mistyping two digits could still slip through, making this statement too broad and not supported.
Answer: B
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02 Feb 2026, 03:25
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I did not quite understand the solution. The option explained and option in the question are totally different.
