Exploring the Ladder Method in Mathematics

The video tutorial introduces the ladder method for finding the greatest common factor (GCF) and least common multiple (LCM) of numbers. It begins with an overview of learning goals and definitions of key terms like composite and prime numbers. Memory tricks for remembering prime numbers are shared. The tutorial then demonstrates the ladder method with examples, calculating the GCF and LCM of 30 and 42, and 12 and 60. The video concludes with a recap of the method and examples.

What is the main goal of the ladder method?

• To find the sum of two numbers

• To find the product of two numbers

• To find the difference between two numbers

• To find the greatest common factor and least common multiple

Which of the following is a composite number?

• 5

• 3

• 2

• 4

Tags

CCSS.4.OA.B.4

What is the first prime number?

• 1

• 2

• 3

• 4

Tags

CCSS.4.OA.B.4

What is the GCF of 30 and 42 using the ladder method?

• 6

• 3

• 2

• 12

What is the LCM of 30 and 42 using the ladder method?

• 120

• 210

• 180

• 240

What is the first step in the ladder method?

• Draw an L shape

• Draw a circle

• Multiply the numbers

• Write the numbers side by side

Tags

CCSS.4.NBT.B.5

What is the GCF of 12 and 60 using the ladder method?

• 24

• 18

• 12

• 6

What is the LCM of 12 and 60 using the ladder method?

• 120

• 90

• 60

• 30

What is the common factor used in the first step for 12 and 60?

• 2

• 3

• 4

• 6

What is the final step in finding the LCM using the ladder method?

• Subtract the numbers

• Multiply all the numbers in the L shape

• Add all the numbers

• Divide the numbers