FINDING LCM AND GCF USING LADDER METHOD

Find the common factors and GCF of the following numbers using the continuous division.

Problem 1 :

Solution :

So, the greatest common factor (GCF) of 24, 36 is  = 2 × 2 × 3

= 12

Problem 2 : 

Solution :

So, the greatest common factor (GCF) of 12, 30, 42 is

= 2 × 3

= 6

Problem 3 : 

Solution :

So, the greatest common factor (GCF) of 28, 32, 40 is 

= 2 × 2

= 4

Problem 4 : 

Solution :

So, the greatest common factor (GCF) of 4, 8, 20 is 

= 2 × 2

= 4

Problem 5 : 

Solution :

So, the greatest common factor (GCF) of 8, 56, 88, 112 is

= 2 × 2

= 4

Give the least common multiple (LCM) using the continuous division.

Problem 6 :

6 and 8 = _____

Solution :

So, the least common multiple (LCM) of 6 and 8 is

= 2 × 3 × 4

= 24

Problem 7 :

3 and 6 = _____

Solution :

So, the least common multiple (LCM) of 3 and 6 is

= 3 × 2 

= 6

Problem 8 :

10 and 4 = _____

Solution :

So, the least common multiple (LCM) of 10 and 4 is

= 2 × 5 ×  2 

= 20

Problem 9 :

8 and 10 = _____

Solution :

So, the least common multiple (LCM) of 8 and 10 is

= 2 × 2 ×  2 × 5

= 40

Problem 10 :

9 and 4 = _____

Solution :

We don't see the common divisor for 9 and 4. So, the least common multiple (LCM) of 9 and 4 is

= 9 × 4

= 36

Find the LCM of these set of numbers using continuous division.

Problem 11 :

8, 12, 24

Solution :

So, the least common multiple (LCM) of 8, 12, 24  is 

= 2 × 2 × 2 × 3 

= 24

Problem 12 :

18, 27, 36

Solution :

So, the least common multiple (LCM) of 18, 27, 36  is

= 3 × 3 × 2 × 3  × 2

= 108

Problem 13 :

9, 12, 18

Solution :

So, the least common multiple (LCM) of 9, 12, 18  is 

= 3 × 3 × 2 × 2

= 36

Problem 14 :

12, 20, 45

Solution :

So, the least common multiple (LCM) of 12, 20, 45  is

= 2 × 3 × 2 × 5 × 3

= 180

Problem 15 :

4, 10, 8

Solution :

So, the least common multiple (LCM) of 4, 10, 8  is

= 2 × 2 × 5 × 2

= 40