Chapter 15 · Class 10 ICSE · Formula Sheet

Ratio & Proportion Formulas — Class 10 ICSE

Apply componendo-dividendo, mean proportion, and continued proportion to solve problems.

Key Formulas

Componendo

\dfrac{a}{b} = \dfrac{c}{d} \implies \dfrac{a+b}{b} = \dfrac{c+d}{d}

Dividendo

\dfrac{a}{b} = \dfrac{c}{d} \implies \dfrac{a-b}{b} = \dfrac{c-d}{d}

Componendo-Dividendo

\dfrac{a+b}{a-b} = \dfrac{c+d}{c-d}

Mean Proportion

b^2 = ac \text{ (b is mean proportion between a and c)}

Worked Examples

1Using: Application

Apply the key formula from this topic to a sample problem.

Step 1: Identify the formula.

Step 2: Substitute the values.

Step 3: Simplify to get the answer.

Answer: See solution above

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More Class 10 ICSE Formulas

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Frequently Asked Questions

How many formulas are in Class 10 ICSE Ratio & Proportion?+
There are 4 formulas in the Ratio & Proportion chapter for Class 10 ICSE. Each formula is essential for solving problems in this topic.
How to remember Ratio & Proportion formulas easily?+
Practice regularly with worked examples, group related formulas together, and use SparkEd's interactive practice mode to reinforce your memory through problem-solving.
Are these Ratio & Proportion formulas enough for exams?+
Yes, these formulas cover the complete ICSE Class 10 syllabus for Ratio & Proportion. Practice applying them to different types of questions for full exam readiness.

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