Last updated at Jan. 3, 2019 by Teachoo

Transcript

Example 13 (Introduction) In a morning walk, three persons step off together. Their steps measure 80 cm, 85 cm and 90 cm respectively. What is the minimum distance each should walk so that all can cover the same distance in complete steps? Let the steps of 3 persons be 1 cm, 2 cm, 3 cm At 6 cm, all of them meet again. Now, this 6 is actually the LCM of 1, 2, 3 So, Distance when they meet again = LCM of 1, 2, 3 Example 13 In a morning walk, three persons step off together. Their steps measure 80 cm, 85 cm and 90 cm respectively. What is the minimum distance each should walk so that all can cover the same distance in complete steps? Steps of 3 persons are 80 cm, 85 cm and 90 cm We need to find, Minimum distance they have walked such that they are together again Now, distance walked by them will be greater than 80, 85, 90 cm. So we find LCM. LCM of 80, 85, 90 LCM = 2 2 2 2 5 3 3 17 = 16 5 9 17 = 80 9 17 = 720 17 = 12240 Minimum distance walked by them = 12240 cm

Statement questions on LCM

How to check if LCM is to be found or HCF

What is the smallest number when divided by numbers 2, 4, 6 gives remainder 0?

What is the smallest number when divided by numbers 2, 4, 6 gives remainder 7?

Example 14 Important

Ex 3.7, 8

Ex 3.7, 4

Ex 3.7, 9 Important

Ex 3.7, 5

Example 13 You are here

What will be the smallest 3-digit number which divides 2, 4, 6 and leaves remainder 0?

Ex 3.7, 2

Ex 3.7, 6 Important

What will be the greatest 3-digit number which divides 2, 4, 6 and leaves remainder 0?

Chapter 3 Class 6 Playing with Numbers

Concept wise

- Factors and Multiples
- Perfect number
- Prime and Composite Numbers
- Sum of prime numbers
- Prime numbers from 1 to 100
- Divisibility Tests - Divisibility by 5, 10, 2
- Divisibility Tests - Divisibility by 4, 8
- Divisibility Tests - Divisibility by 3, 6, 9
- Divisibility Tests - Divisibility by 11
- Divisibility Tests - All
- Common Multiples
- Common Factors
- More Divisibility Rules
- Factor Tree
- Prime Factorisation
- Highest Common Factor
- Lowest Common Multiple
- Statement questions on LCM
- Statement questions on HCF

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.