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Last updated at Sept. 11, 2018 by Teachoo

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Ex 6.3, 10 Find the smallest square number that is divisible by each of the numbers 8, 15 and 20.Smallest square number divisible by 8, 15, 20 = L.C.M of 8, 15, 20 Or Multiple of L.C.M Finding L.C.M of 8, 15, 20 L.C.M of 8, 15, 20 = 2 × 2 × 2 × 3 × 5 = 4 × 6 × 5 = 4 × 30 = 120 Checking if 120 is a perfect square We see that, 120 = 2 × 2 × 2 × 3 × 5 Here, 2, 3 & 5 do not occur in pairs ∴ 120 is not a perfect square So, we multiply by 2, 3 and 5 to make pairs So, our number becomes 120 × 2 × 3 × 5 = 2 × 2 × 2 × 3 × 5 × 2 × 3 × 5 3600 = 2 × 2 × 2 × 2 × 3 × 3 × 5 × 5 Now, it becomes a perfect square. So, required number is 3600

Chapter 6 Class 8 Squares and Square Roots

Concept wise

- Square numbers
- Properties of square numbers
- Sum of consecutive odd numbers
- Numbers between square numbers
- Pattern Solving
- Finding square of large numbers
- Pythagorean triplets
- Square root
- Finding Square root through repeated subtraction
- Finding Square root through prime factorisation
- Checking if perfect square by prime factorisation
- Smallest number multiplied to get perfect square
- Smallest number divided to get perfect square
- Smallest square number divisible by numbers
- Finding number of digits in square root (without calculation)
- Finding square root by division method - Integers
- Least number subtracted to get a perfect square
- Least number added to get a perfect square
- Finding square root by division method - Decimals
- Statement Questions

About the Author

Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.