Multiples And Factors (GCF, LCM)
Overview
Break any whole number apart and you find the prime numbers hiding inside it. This prime fingerprint is unique to every number, and it is the key to two of the most useful ideas in arithmetic: the greatest common factor that two numbers share, and the least common multiple at which their times tables first meet.
In this lesson you will write numbers as products of their prime factors, then use that factorization to find the GCF and LCM quickly and reliably. These skills cancel fractions to their simplest form, add fractions with different denominators, and solve a host of timing and grouping problems.
Objectives
- Find the greatest common factor (GCF) and least common multiple (LCM) of two or more numbers, including by prime factorization.
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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 Multiples And Factors (GCF, LCM). 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 the prime factorization of 60? A. 2 x 3 x 10 B. 2^2 x 3 x 5 C. 2 x 30 D. 4 x 15 Answer: B
- What is the GCF of 24 and 60? A. 6 B. 8 C. 12 D. 120 Answer: C
- What is the LCM of 24 and 60? A. 12 B. 60 C. 120 D. 1440 Answer: C
- Which of these is a multiple of 4? A. 6 B. 10 C. 14 D. 16 Answer: D
- Two bells ring every 6 and 8 minutes. After how many minutes do they next ring together? A. 2 B. 14 C. 24 D. 48 Answer: C
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