Finding LCM & GCF with the Ladder Method

This video tutorial explains how to find the greatest common factor (GCF) and the least common multiple (LCM) of a set of numbers using the ladder method. It begins with an introduction to the concepts of GCF and LCM, followed by a detailed explanation of the ladder method. The video demonstrates finding the GCF of 18 and 30, and then calculating the LCM using the same numbers. The tutorial concludes with a brief apology for any sloppiness in the presentation.

What does GCF stand for?

• Greatest Common Function

• Greatest Common Formula

• Greatest Common Fraction

• Greatest Common Factor

What is required to find the GCF or LCM?

• One number

• Two or more numbers

• Three numbers

• Four numbers

What shape is drawn in the ladder method?

• Triangle

• L-shape

• Square

• Circle

Tags

CCSS.7.EE.B.3

What is the first common factor of 18 and 30 in the ladder method?

• 2

• 5

• 3

• 7

What are the numbers 9 and 15 both divisible by?

• 7

• 2

• 5

• 3

Tags

CCSS.4.OA.B.4

What is the GCF of 18 and 30?

• 6

• 3

• 9

• 12

What is the LCM of 18 and 30?

• 60

• 70

• 80

• 90

Which property is applied to make multiplication easier?

• Commutative property

• Associative property

• Identity property

• Distributive property

Tags

CCSS.4.NBT.B.5

What is the result of multiplying 2 and 5?

• 7

• 9

• 10

• 12

Tags

CCSS.3.OA.C.7

What is the final step in the ladder method?

• Drawing the ladder

• Finding the GCF

• Finding the LCM

• Listing out the factors