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Ex 7.1, 2 - Chapter 7 Class 8 Cubes and Cube Roots - Part 9

Ex 7.1, 2 - Chapter 7 Class 8 Cubes and Cube Roots - Part 10

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Ex 7.1, 2 Find the smallest number by which each of the following numbers must be multiplied to obtain a perfect cube. (v) 100 We see that 100 = 2 × 2 × 5 × 5 Since 2 & 5 does not occur in triplets, ∴ 100 is not a perfect cube. So, we multiply by 2 × 5 to make triplet So, our number becomes 100 × 2 × 5 = 2 × 2 × 5 × 5 × 2 × 5 = 2 × 2 × 2 × 5 × 5 × 5 Now, it becomes a perfect cube. So, we multiply 100 by 2 × 5 i.e. 10 to make it a perfect cube

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