Lesson Notes By Weeks and Term v4 - JHS 2

Lesson Video

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Performance objectives

• Define what a ratio is and provide examples.
• Convert measurement units using ratio reasoning.
• Solve problems involving ratios and proportions.
• Apply your understanding of ratios in real-life scenarios.

Lesson summary

This lesson focuses on a very practical and important mathematical skill: using ratios to convert between different units of measurement. In our daily lives in Ghana, we constantly encounter different units. A tailor buys fabric in metres but measures it in centimetres. A cook buys rice in kilograms but might measure it for a recipe in grams. A driver measures a long journey in kilometres, but a short distance in metres. Understanding how to confidently convert between these units using the concept of ratios is essential for accuracy in shopping, cooking, construction, and many other activities.

Lesson notes

A. What is a Ratio? (A Quick Recap)

A ratio is a way of comparing two or more quantities of the same kind. For example, if there are 3 boys and 5 girls in a group, the ratio of boys to girls is 3:5 or 3/5. B. What is a "Conversion Ratio"?

A Conversion Ratio is a special type of ratio that compares two quantities that are equal in value but are expressed in different units. This ratio is the key to converting measurements.

Key Conversion Ratios to Know: