B. If this month is not September, then next month does not end in the letter r. The converse is true.


C.If next month ends in the letter r, then this month is September. The converse is false; a counterexample is December.

D. If this month is not September, then next month does not end in the letter r. The converse is false; a counterexample is December.

1 answer

Let's analyze the statements you've provided.

Statement B

  • Original Statement: If this month is not September, then next month does not end in the letter “r.”
  • Converse: If next month ends in the letter “r,” then this month is September.

Analysis:

  1. When is the original statement true?

    • It is true for all months except for August (which is not September, but next month is September, which ends in “r”).
  2. When is the converse true?

    • The converse is true because if next month ends in the letter “r,” it must be September, making this month's condition correct as well.

Statement C

  • Original Statement: If next month ends in the letter “r,” then this month is September.
  • Converse: If this month is not September, then next month does not end in the letter “r.”

Analysis:

  1. When is the original statement true?

    • The original statement is true because if next month ends in "r" (i.e., September, December, or such), this month must be August or November, respectively, making the month not September.
  2. When is the converse false?

    • A counterexample is given: December, where this month is not September, but the next month (January) ends in "r."

Statement D

  • Original Statement: If this month is not September, then next month does not end in the letter “r.”
  • Converse: If next month ends in the letter “r,” then this month is September.

Analysis:

  1. When is the original statement true?

    • Like B, it is not true if this month is August, because next month will be September which does end in "r."
  2. When is the converse false?

    • The counterexample provided is again December, because even though this month is not September, January ends in "r."

Summary:

  • Statement B is true and its converse is true.
  • Statement C is logically consistent in that the original is true, and the converse is indeed false (the December counterexample stands).
  • Statement D contains an original statement that is the same as B (true) and provides a converse that is the same as C (false).

Thus, statements B and D are effectively discussing the same premise regarding September and the months that follow, while C explores the implications of next months ending in "r" correctly.