Skip to main content
Chapter 1 of 15
Flashcards

Real Numbers

Kerala Board · Class 9 · Mathematics

Flashcards for Real Numbers — Kerala Board Class 9 Mathematics. Quick Q&A cards covering key concepts, definitions, and formulas.

45 questions20 flashcards5 concepts
20 Flashcards
Card 1Decimal Representation

Express 7/16 in decimal form and classify it.

Answer

Step 1: Divide 7 by 16 using long division. Step 2: 7 ÷ 16 = 0.4375 Step 3: Since decimal terminates, it's a terminating decimal. Answer: 0.4375 (terminating decimal, rational number) Why it terminate

Card 2Converting Decimals to Fractions

Convert the recurring decimal 0.36̄ to p/q form.

Answer

Step 1: Let x = 0.363636... Step 2: Multiply by 100: 100x = 36.363636... Step 3: Subtract: 100x - x = 36.363636... - 0.363636... Step 4: 99x = 36 Step 5: x = 36/99 = 4/11 (simplifying by dividing by 9

Card 3Finding Rational Numbers

Find three rational numbers between 2/3 and 3/4 using the mean method.

Answer

Step 1: First rational = (2/3 + 3/4)/2 = (8/12 + 9/12)/2 = 17/24 Step 2: Second rational = (2/3 + 17/24)/2 = (16/24 + 17/24)/2 = 33/48 = 11/16 Step 3: Third rational = (17/24 + 3/4)/2 = (17/24 + 18/24

Card 4Irrational Numbers

Prove that √3 is an irrational number using contradiction method.

Answer

Step 1: Assume √3 is rational, so √3 = p/q where p, q are integers with no common factors. Step 2: Squaring both sides: 3 = p²/q², so p² = 3q² Step 3: This means 3 divides p², so 3 divides p. Let p =

Card 5Square Root Calculation

Find the value of √2 up to 3 decimal places using long division.

Answer

Step 1: Set up 2.000000 under the radical sign Step 2: Find largest digit whose square ≤ 2: 1² = 1 Step 3: Subtract and bring down: 2 - 1 = 1, bring down 00 → 100 Step 4: Double the quotient (1) = 2,

Card 6Representing Irrational Numbers

Locate √5 on the number line using geometric construction.

Answer

Step 1: Draw a number line with O at origin Step 2: Mark unit square OABC with OA = OC = 1 Step 3: By Pythagoras: OB = √(1² + 1²) = √2 Step 4: Draw BD perpendicular to OB with BD = 1 Step 5: By Pythag

Card 7Operations with Surds

Simplify: (3 + √5)(2 - √5)

Answer

Step 1: Use FOIL method (First, Outer, Inner, Last) Step 2: First: 3 × 2 = 6 Step 3: Outer: 3 × (-√5) = -3√5 Step 4: Inner: √5 × 2 = 2√5 Step 5: Last: √5 × (-√5) = -5 Step 6: Combine: 6 - 3√5 + 2√5 -

Card 8Rationalization

Rationalize the denominator: 1/(3 + √2)

Answer

Step 1: Multiply numerator and denominator by conjugate (3 - √2) Step 2: = (1 × (3 - √2))/((3 + √2)(3 - √2)) Step 3: Denominator: (3 + √2)(3 - √2) = 3² - (√2)² = 9 - 2 = 7 Step 4: Numerator: 1 × (3 -

+12 more flashcards available

Practice All

Get detailed flashcards for Real Numbers

Super Tutor gives you interactive content for every chapter of Kerala Board Class 9 Mathematics — summaries, quizzes, flashcards, and more.

Try Super Tutor — It's Free

Frequently Asked Questions

What are the important topics in Real Numbers for Kerala Board Class 9 Mathematics?

Real Numbers covers several key topics that are frequently asked in Kerala Board Class 9 board exams. Focus on the core concepts listed on this page and practise related questions to build confidence.

Start by understanding all key concepts. Practise previous year questions from this chapter. Revise formulas and definitions regularly. Use flashcards for quick revision before the exam.

There are 20 flashcards for Real Numbers covering key definitions, formulas, and concepts. Use them daily for 10–15 minutes for best results.

Sources & Official References

Content is aligned to the official syllabus. Refer to the board website for the latest curriculum.