CBSE MATHEMATICS • SELECTED CENTRAL & STATE COMPETITIVE EXAMS
AIMSSchool of MathematicsAim through AIMS

GANITA MANJARI · GRADE 9 · PART II · CHAPTER 9

STATE — What Is a Proposition?

Think first. Use AI purposefully. Verify always.

01 · DISCOVER

Start by thinking.

Compare “14 is even”, “Is 14 even?” and “Divide 14 by 2”. Which says something that can be judged true or false?

Try 1 of 3: “26 is a multiple of 3.”

Classify first.

02 · UNDERSTAND

What Is a Proposition?

A proposition makes a complete statement with a truth value. It can be true or false: being false does not stop it being a proposition. A question asks for information; an instruction asks for an action. An expression alone does neither.

03 · KEY IDEAS

Keep the conditions clear.

  • A complete statement can be tested as true or false.
  • Questions, commands and unfinished expressions are not propositions.
  • An unspecified variable may leave a statement incomplete: state the value or the condition first.

04 · VISUALISE

Follow the direction.

Complete statement → proposition → judge true or false. A question or instruction follows a different path.

05 · METHOD / REASONING

Make the argument checkable.

Read the whole sentence. Ask whether it states something, then decide whether there is enough information to judge it. Classify before deciding truth.

06 · ORIGINAL AIMS WORKED EXAMPLE

Follow each step.

Classify “27 is a multiple of 4”, “Find a multiple of 4” and “27 +”.

  1. The first is a complete statement: it is a proposition.
  2. Since 27 = 4 × 6 + 3, that proposition is false.
  3. The second is an instruction; the third is unfinished. Neither has a truth value.

07 · AIMS METHOD

Your turn to reason.

  1. Attempt independently
  2. Investigate the idea
  3. Make connections
  4. Scrutinise your reasoning

Is “Every square has five sides” a proposition?

Compare after your own attempt

Yes, a false proposition. A square has four sides.

08 · PRACTICE SPRINT

Use the idea in a new situation.

Ten original AIMS questions: 3 Warm-up, 4 Build, 2 Think and 1 Challenge.

Start Practice Sprint →

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.

All textbook references →