Percentages
Overview
Percentages are the language money speaks. A discount in a sale, the interest on a loan, a test score, a pay rise, the VAT on a receipt: all of them are percentages, and being quick with them is one of the most useful everyday skills mathematics gives you. A percentage is simply a fraction out of 100, which is exactly what makes comparisons so easy.
In this lesson you will learn to find a percentage of an amount, write one quantity as a percentage of another, and handle percentage increases and decreases with confidence. You will then meet the two ideas examiners love to test: the difference between simple and compound interest, and reverse percentages, where you work backwards from the final amount to the original. Master these and a whole class of exam questions becomes routine.
Objectives
- Calculate a given percentage of a quantity.
- Express one quantity as a percentage of another.
- Calculate percentage increase or decrease.
- Calculate with simple and compound interest.
- Calculate using reverse percentages. (Extended only)
Audio Lesson
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Mind map
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Flashcards
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Lesson Note
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Lesson Evaluation
Congratulations on completing the lesson on Percentages. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- What is 15% of 240? A. 16 B. 36 C. 255 D. 360 Answer: B
- A jacket costing $80 is reduced by 15% in a sale. What is the sale price? A. $12 B. $65 C. $68 D. $92 Answer: C
- A student scored 18 out of 40 in a test. What percentage is this? A. 18% B. 22% C. 40% D. 45% Answer: D
- $2000 is invested at 5% per year compound interest. What is the value after 2 years? A. $2100.00 B. $2200.00 C. $2205.00 D. $2210.00 Answer: C
- After a 20% reduction, a coat costs $96. What was the original price? A. $76.80 B. $115.20 C. $120.00 D. $480.00 Answer: C
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