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Review of arithmetic with fractions II | Year 9 Maths 3 | NJ Wildberger

2,490 views · Published 17 February 2014 · 48:14 · Indexed 8 October 2026

Channel: Insights into Mathematics · 2014 · Education

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This is a review video meant for Year 9 students. We go over arithmetic with fractions, making sure you know all the basic operations and what they mean geometrically. For us, fractions correspond to positions on a number line, and the arithmetical operations of addition, multiplication, subtraction and division can all be interpreted in this context.

it is very important for Year 9 students to have a good working knowledge of this material. Make sure you do the exercises, to test your understanding!

Video Content:
00:00 Intro to fractions
8:09 How to add/subtract fractions with different denominators
12:28 Simpler common denominators
18:50 General formulas for addition and subtraction
23:15 Multiplication
28:29 Multiplying two fractions
36:17 Division
38:34 The reciprocal of a fraction

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