Compare “multiple of 10 implies multiple of 5” with its reverse. Must the two directions receive the same verdict?
02 · UNDERSTAND
Proposition and Converse Together
Judge the proposition and its converse separately. We study true/false, true/true and false/false pairs. These are not the only possible arrangements; a false proposition can have a true converse.
03 · KEY IDEAS
Keep the conditions clear.
Each true direction needs a reason.
Each false direction needs its own valid counterexample.
Changing the starting direction exchanges the two verdicts.
04 · VISUALISE
Follow the direction.
For divisibility use positive integers; for the equation use real x.
Proposition
If n is a multiple of 10, then n is a multiple of 5.
Converse
If n is a multiple of 5, then n is a multiple of 10.
Your explanation is for self-review; AIMS does not automatically grade written reasoning.
05 · METHOD / REASONING
Make the argument checkable.
Write both directions side by side. For each, give a general reason or a counterexample before naming the pair.
06 · ORIGINAL AIMS WORKED EXAMPLE
Follow each step.
For positive integers, compare “multiple of 4 implies multiple of 10” and its converse.
4 is a multiple of 4 but not of 10: the original is false.
10 is a multiple of 10 but not of 4: the converse is false.
A shared multiple such as 20 supports both statements in one case but proves neither universal claim.
07 · AIMS METHOD
Your turn to reason.
AAttempt independently
IInvestigate the idea
MMake connections
SScrutinise your reasoning
Can a proposition be false while its converse is true?
Compare after your own attempt
Yes. “Rectangle implies square” is false; “square implies rectangle” is true.
08 · PRACTICE SPRINT
Use the idea in a new situation.
Ten original AIMS questions: 3 Warm-up, 4 Build, 2 Think and 1 Challenge.
Check & Feedback: incorrect answers receive a conceptual hint and another attempt; correct answers include reasoning.
TEXTBOOK CONNECTION
Return to the source. Bring your reasoning.
Ganita Manjari · Grade 9 · Part II · Chapter 9. Use your textbook for the complete questions. These are topic references and original AIMS guidance, not reproduced exercises.
Exercise Practice
Exercise Set 9.1 · Q2
Source page 5 · COMPARE
Squares and equal-angle quadrilaterals
Check whether angle information also forces all four side lengths equal.
AIMS reasoning checkpoint
A non-square rectangle distinguishes the two directions.