Exploring Common Denominators in Rational Expressions

This video tutorial explains the concept of common denominators, which are crucial for adding, subtracting, and comparing fractions. It outlines the steps to find common denominators: listing multiples, finding the least common multiple (LCM), and adjusting numerators. The video provides examples and a practice exercise to reinforce learning. Understanding common denominators is essential for working with fractions effectively.

Why is it important to find common denominators?

• To simplify fractions

• To add, subtract, and compare fractions

• To multiply fractions

• To divide fractions

Tags

CCSS.5.NF.A.1

CCSS.5.NF.A.2

What is the denominator in a fraction?

• The decimal part

• The whole number

• The bottom number

• The top number

Tags

CCSS.3.NF.A.1

CCSS.3.NF.A.2B

What is the first step in finding common denominators?

• Convert to improper fractions

• Find the greatest common divisor

• List the multiples of each denominator

• Adjust the numerators

What are the multiples of 6?

• 7, 14, 21, 28, 35

• 5, 10, 15, 20, 25

• 6, 12, 18, 24, 30

• 8, 16, 24, 32, 40

What is the least common multiple (LCM) of 5 and 6?

• 18

• 30

• 12

• 60

How do you adjust the numerator when the denominator is multiplied by 5?

• Add 5 to the numerator

• Subtract 5 from the numerator

• Multiply the numerator by 5

• Divide the numerator by 5

Tags

CCSS.5.NF.B.5B

What is the equivalent fraction of 2/6 when the denominator is 30?

• 2/30

• 12/30

• 10/30

• 5/30

Tags

CCSS.3.NF.A.3B

CCSS.4.NF.A.1

What is the least common multiple (LCM) of 9 and 6?

• 27

• 18

• 36

• 54

What is the equivalent fraction of 2/9 when the denominator is 18?

• 8/18

• 6/18

• 2/18

• 4/18

Tags

CCSS.3.NF.A.3B

CCSS.4.NF.A.1

Why is finding common denominators important?

• To divide fractions

• To simplify fractions

• To add, subtract, and compare fractions

• To multiply fractions

Tags

CCSS.5.NF.A.1

CCSS.5.NF.A.2