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5 courses
88 practices
6 hours
Master factors, multiples, and prime factorization. Learn rapid divisibility tests and calculate HCF and LCM to solve real-world grouping, sharing, and scheduling challenges with precision.
You'll build fluency with factors, factor pairs, and multiples, and learn to classify whole numbers greater than 1 as prime or composite, while recognizing 1 as neither, — the essential foundation for all later work with divisibility and prime factorisation.
You'll master quick divisibility tests for 2, 3, 4, 5, 6, 9, and 10 — learning to tell at a glance whether a number is divisible by any of these and understanding why each shortcut works in base ten.
You'll learn to break any composite number into its prime factors using factor trees and repeated division, then express the result compactly and clearly using index notation.
You'll identify common factors and determine the Highest Common Factor of two or more numbers using factor lists and prime factorisation, then apply HCF reasoning to practical equal-sharing and grouping problems.
You'll find common multiples and the Lowest Common Multiple using listing and prime factorisation methods, apply LCM to repeating-cycle problems, and learn to choose confidently between HCF and LCM in any situation.
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