CBSE MATHEMATICS • SELECTED CENTRAL & STATE COMPETITIVE EXAMS
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GANITA PRAKASH · GRADE 8 · PART II · CHAPTER 1

CONVERT — Fractions, decimals and percentages

Think first. Use AI purposefully. Verify always.

DISCOVER

Begin with a prediction.

Can 0.25, one quarter and 25% describe the same amount? Sketch evidence.

Sketch or write an independent attempt before reading on. Test your idea using the model.

Understand

Fractions, decimals and percentages are different representations of a number. A recurring decimal may need an approximation; a fraction can preserve the exact value.

Key Ideas

24%=24100=625=0.24

0.5 means 50%, not 0.5%. One third is exactly 1003%, approximately 33.33%.

Visualise

One value, three representations

Predict first. Change the controls, then compare your reasoning.

Method

Fraction to decimal: divide numerator by denominator. Decimal to percentage: multiply by 100 and attach %. Percentage to decimal: divide by 100.

Worked Example

Given

A share of 24%.

To Find

The equivalent simplified fraction and decimal

Reasoning

Percent means divided by 100.

Solution

  1. 24% = 24100.
  2. Divide numerator and denominator by 4: 625.
  3. 24 ÷ 100 = 0.24.

Result

24% = 625 = 0.24.

AIMS Method

  1. A — Attempt independently
    Estimate and predict first.
  2. I — Investigate the idea
    Identify the whole and the percentage base.
  3. M — Make connections
    Connect fractions, decimals, bars and multipliers.
  4. S — Scrutinise your reasoning
    Check units, bases and the reasonableness of the result.

Think first. Use AI purposefully. Verify always.

Focused Practice

Convert 920 to a percentage and a decimal. Check using an equivalent fraction.

Continue with CONVERT →

Check & Feedback

Name the whole, explain the method and give one check that would catch a wrong percentage base.

Textbook connection: Ganita Prakash · Grade 8 · Part II · Fractions in Disguise · printed page 8