Adding and Subtracting Fractions with Unlike Denominators

This video tutorial teaches how to add and subtract fractions with unlike denominators. It introduces the method of rewriting problems vertically and finding the least common multiple (LCM) to make equivalent fractions. The tutorial covers both addition and subtraction of fractions, including simplifying results and converting improper fractions to mixed numbers. The instructor provides step-by-step examples to ensure understanding.

What is the first step in solving a fraction problem with unlike denominators?

• Multiply the fractions

• Find the greatest common divisor

• Rewrite the problem vertically

• Add the numerators

Tags

CCSS.7.NS.A.1C

What does LCM stand for?

• Largest Common Measure

• Least Common Measure

• Least Common Multiple

• Largest Common Multiple

How do you find the LCM of two numbers?

• Multiply the two numbers together

• Subtract the smaller number from the larger one

• Add the two numbers together

• List out the multiples of each number and find the smallest common one

What is the LCM of 3 and 5?

• 25

• 20

• 15

• 10

How do you make equivalent fractions once you have the LCM?

• Divide the numerator by the LCM

• Subtract the LCM from the denominator

• Multiply both the numerator and denominator by the same number

• Add the LCM to the numerator

Tags

CCSS.3.NF.A.3A

CCSS.3.NF.A.3B

CCSS.4.NF.A.1

What should you do if the result of adding fractions is an improper fraction?

• Subtract the numerator from the denominator

• Leave it as it is

• Convert it to a mixed number

• Multiply it by the LCM

Tags

CCSS.5.NF.A.1

CCSS.5.NF.A.2

What is the LCM of 8 and 6?

• 30

• 24

• 18

• 12

What is a common error students make when subtracting fractions?

• Dividing the fractions

• Adding instead of subtracting

• Forgetting to find the LCM

• Multiplying the fractions

Tags

CCSS.5.NF.A.1

CCSS.5.NF.A.2

How do you simplify the fraction 4/12?

• Divide both the numerator and denominator by 4

• Divide both the numerator and denominator by 3

• Multiply both the numerator and denominator by 2

• Divide both the numerator and denominator by 2

What is the simplified form of 6/8?

• 3/5

• 2/3

• 1/2

• 3/4