Lesson 5: Revision and Practice

📥 Introduction

Congratulations! 🎉 You’ve learned about fractions, decimals, ratios, percentages, rates, and taxes.
Now it’s time to pull everything together, review the key concepts, and test yourself with mixed practice questions!

🧠 Quick Concept Review

Fractions

• A fraction shows parts of a whole.
• To add/subtract fractions: Find a common denominator.
• To multiply fractions: Multiply across.
• To divide fractions: Flip the second fraction and multiply.

Decimals

• Decimals show parts of a whole using place value (tenths, hundredths, thousandths).
• Line up decimal points when adding or subtracting.
• Multiply normally, then adjust decimal places.
• To divide decimals, make the divisor a whole number first.

Ratios and Proportions

• A ratio compares two or more quantities.
• Proportions are two equal ratios — solved by cross-multiplication.
• Always simplify ratios where possible.

Percentages, Rates, and Taxes

• Percentage = “per hundred.”
• Rate = comparison between two different units (e.g., km/hour).
• Tax = an extra percentage added to price or income.

✅ Final Practice Test

A. Fractions and Decimals

• Simplify .
• Add: .
• Convert 0.72 to a fraction and simplify.
• Multiply: .

B. Ratios and Proportions

• Simplify the ratio 36:48.
• If , find x.
• The ratio of boys to girls in a club is 5:3. If there are 40 boys, how many girls?

C. Percentages, Rates, and Taxes

• Find 12% of 450.
• A taxi travels 240 km in 4 hours. What is its speed in km/h?
• If a phone costs GHS 850 and VAT is 6%, find the total price including tax.
• Convert 0.45 to a percentage.

D. True or False?

• 
• 70% is greater than 3/4.
• 8:12 simplifies to 2:3.
• 6% of 200 is 12.

🔑 Answer Key (Quick Check)

• A: 3/4, 9/10, 18/25, 3/10
• B: 3:4, x = 6, 24 girls
• C: 54, 60 km/h, GHS 901, 45%
• D: True, False, True, True

🔁 Final Recap

• Fractions, decimals, ratios, percentages, rates, and taxes are powerful everyday tools!
• Understand how to switch between forms, solve problems, and apply them to real-world situations.
• Always check if your answers make sense based on the question.

🪞Final Reflection Prompt

Which topic in Module 3 do you feel strongest about? Which topic do you want to practice a little more? Set a mini-goal to practice 5 more problems on your own!