Understanding Addition of Fractions with Unlike Denominators

This video tutorial explains how to add fractions with unlike denominators by finding a common denominator. It covers the concept of the least common denominator, using prime factorization to find it, and creating equivalent fractions. The tutorial also demonstrates how to add the fractions and simplify the result.

Why is it necessary to find a common denominator when adding fractions?

• To simplify the fractions

• To make the fractions look similar

• To add or subtract parts of the same size

• To ensure the fractions have the same numerator

What is the least common denominator?

• The sum of the two denominators

• The smallest number that is a multiple of both denominators

• The smallest number that is a multiple of both numerators

• The largest number that divides both denominators

How can you find a common denominator if the least common multiple is too large?

• By multiplying the denominators

• By subtracting the denominators

• By using prime factorization

• By adding the denominators

What is the prime factorization of 15?

• 5 x 5

• 2 x 3

• 2 x 7

• 3 x 5

Tags

CCSS.5.NF.A.1

CCSS.5.NF.A.2

What is the next step after finding the prime factors of the denominators?

• Multiply the numerators

• Ensure both denominators have the same prime factors

• Subtract the numerators

• Add the numerators

How do you create an equivalent fraction with a common denominator?

• By subtracting the same number from both numerator and denominator

• By dividing the numerator and denominator by the same number

• By adding the same number to both numerator and denominator

• By multiplying the numerator and denominator by the missing factors

Tags

CCSS.5.NF.A.1

CCSS.5.NF.A.2

What is the sum of 2/15 and 1/24 when expressed with a common denominator?

• 16/120

• 5/120

• 21/120

• 7/40

What common factor do 21 and 120 share?

• 3

• 2

• 5

• 4

How can you simplify the fraction 21/120?

• By adding 3 to both numerator and denominator

• By dividing both numerator and denominator by 3

• By subtracting 3 from both numerator and denominator

• By multiplying both numerator and denominator by 3

What is the simplified form of 21/120?

• 1/40

• 3/40

• 7/40

• 21/40