Greatest Common Factor Using the Ladder Method

This video tutorial explains how to find the greatest common factor (GCF) using the ladder method. It begins with an introduction to the concept of GCF, also known as the greatest common denominator or highest common factor, and explains that it is the largest whole number that divides evenly into two or more numbers. The tutorial then demonstrates the ladder method through three examples: finding the GCF of 40 and 24, 65 and 120, and 36 and 78. Each example is broken down step-by-step, showing how to divide the numbers and multiply the factors to find the GCF.

What is the Greatest Common Factor (GCF)?

• The product of two numbers

• The sum of two numbers

• The largest number that divides two numbers

• The smallest number that divides two numbers

Which method is used in the video to find the GCF?

• Prime Factorization

• Division Method

• Ladder Method

• Subtraction Method

What is the first step in finding the GCF of 40 and 24 using the ladder method?

• Find a common divisor

• Add the numbers

• Multiply the numbers

• Subtract the numbers

What is the GCF of 40 and 24?

• 8

• 6

• 4

• 10

Which number is used to divide both 65 and 120 in the ladder method?

• 2

• 3

• 5

• 4

What is the GCF of 65 and 120?

• 10

• 5

• 20

• 15

Tags

CCSS.3.OA.D.9

What rule is used to determine if 3 divides 36 and 78?

• If the number is even

• If the number ends in 3

• If the number is odd

• If the sum of digits is divisible by 3

What is the GCF of 36 and 78?

• 15

• 9

• 12

• 6

Tags

CCSS.4.NBT.B.6

CCSS.5.NBT.B.6

What is the final step in the ladder method?

• Divide the numbers on the outside

• Add the numbers on the outside

• Multiply the numbers on the outside

• Subtract the numbers on the outside

What is the purpose of the ladder method?

• To find the average of numbers

• To find the sum of numbers

• To find the greatest common factor

• To find the least common multiple