Estimation
Overview
An estimate is a quick, sensible answer that tells you roughly what to expect, and it is one of the most practical skills in mathematics. It lets you check a calculator answer in seconds and catch the kind of mistake that turns 4.2 into 42.
In this lesson you will round numbers to a given number of decimal places or significant figures, make estimates by rounding to one significant figure, and round final answers to a sensible accuracy for the problem. Estimation is the habit that keeps your answers believable.
Objectives
- Round values to a specified degree of accuracy.
- Make estimates for calculations involving numbers, quantities and measurements.
- Round answers to a reasonable degree of accuracy in the context of a given problem.
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 Estimation. 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.
- Round 3.14159 to 2 decimal places. A. 3.1 B. 3.14 C. 3.142 D. 3.15 Answer: B
- Round 0.04736 to 2 significant figures. A. 0.04 B. 0.047 C. 0.05 D. 0.0474 Answer: B
- Estimate 38.2 x 5.9 รท 2.1 by rounding each number to 1 significant figure. A. 12 B. 60 C. 120 D. 1200 Answer: C
- How many significant figures does 0.0205 have? A. 2 B. 3 C. 4 D. 5 Answer: B
- Round 4827 to 2 significant figures. A. 48 B. 4800 C. 4830 D. 5000 Answer: B
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