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Part CCSIR NET December 202531-days-beats-30-possible-borrower-lender-pairs-by-exactly-one-thats-the-whole-mechanism

31 days beats 30 possible borrower lender pairs by exactly one thats the whole mechanism

There are six persons. On each day of the year 2024 at least one of them borrowed money from another. A person P is labeled troublesome in a calendar month M of 2024 if P borrowed from the same person at least twice during month M. Which of the following statements are necessarily true?

  1. A.In every calendar month of 2024, at least one person was troublesome.
  2. B.In any two consecutive calendar months of 2024, at least one person was troublesome in at least one of the two calendar months.✓ Correct
  3. C.At least one person was troublesome in two calendar months of 2024.✓ Correct
  4. D.At least one person was troublesome in January 2024.✓ Correct

You have the answer. Trap Analysis is why the other three were written.

Not a worked solution repeated four times — the specific reasoning error each wrong option was built to reward, and why this one tests boundary and endpoint.

See pricing

50 are analysed free — try those first.

The trap it tests

Boundary and endpoint

The statement turns at the edge of the interval, the domain, or the parameter range.

Drill statements like this

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