Fractions: Addition and Subtraction

The video tutorial covers the process of adding and subtracting fractions, emphasizing the importance of finding a common denominator. It explains how to use the least common multiple and prime factorization to determine the least common denominator. The tutorial provides examples of both addition and subtraction of fractions, including simplifying the results. It also includes more complex examples that require prime factorization to find the least common denominator.

What is the first step in adding fractions with different denominators?

• Multiply the fractions.

• Add the numerators directly.

• Find a common denominator.

• Subtract the smaller fraction from the larger one.

When adding 3/5 and 1/6, what is the least common denominator?

• 15

• 10

• 30

• 60

How do you find the least common denominator using prime factorization?

• Divide the larger denominator by the smaller one.

• Identify the highest power of each prime factor present in the denominators.

• Multiply the numerators by the prime factors.

• Add the prime factors of both denominators.

What is the simplified form of the sum of 12/27 and 2/9?

• 1/2

• 2/3

• 4/9

• 5/9

What must be true about the denominators when subtracting fractions?

• They must be the same.

• They must be prime numbers.

• They must be different.

• One must be a multiple of the other.

In the example of subtracting 1/2 from 3/10, what is the least common denominator?

• 20

• 15

• 10

• 5

How do you determine the least common denominator using prime factorization for subtraction?

• Add the numerators.

• Use the highest power of each prime factor present in the denominators.

• Subtract the smaller denominator from the larger one.

• Multiply the denominators together.

What is the simplified form of the difference between 19/42 and 13/70?

• 2/7

• 4/15

• 5/21

• 3/14

What is the purpose of simplifying fractions after addition or subtraction?

• To make the fraction larger.

• To make calculations easier.

• To express the fraction in its simplest form.

• To change the fraction to a decimal.

Which of the following is a common factor used in simplifying fractions?

• 1

• 2

• 10

• 0