Understanding Subtraction and Addition of Fractions

The video tutorial explains how to solve a fraction subtraction problem by converting it into an addition problem using the concept of opposites. It highlights the importance of not using the associative property with subtraction and demonstrates how to find a common denominator and the least common multiple to simplify the calculation. The solution is presented step-by-step, ensuring a clear understanding of the process.

Why can't we use the associative property directly in subtraction?

• Because subtraction is not associative.

• Because subtraction is the same as addition.

• Because subtraction is commutative.

• Because subtraction is distributive.

What is the equivalent of subtracting a negative number?

• Adding a negative number.

• Multiplying by zero.

• Adding a positive number.

• Subtracting a positive number.

What is the result of adding 7/3 and -11/3?

• -2/3

• 0

• -4/3

• 4/3

Why do we need a common denominator when adding fractions?

• To ensure the fractions are comparable.

• To make the fractions larger.

• To change the fractions to whole numbers.

• To simplify the fractions.

What is the least common multiple of 7 and 3?

• 10

• 14

• 21

• 28

How do you convert 3/7 to a fraction with a denominator of 21?

• Subtract 4 from the denominator.

• Add 14 to the numerator.

• Multiply both numerator and denominator by 7.

• Multiply both numerator and denominator by 3.

What is the result of 9 minus 28 over 21?

• -19/21

• 19/21

• 0

• 9/21

What is the final simplified result of the problem?

• 0

• 9/21

• -19/21

• 19/21

What operation is equivalent to adding a negative number?

• Subtracting a positive number.

• Dividing by one.

• Multiplying by zero.

• Adding a positive number.

What is the importance of finding a common denominator in fraction operations?

• It changes the fractions to whole numbers.

• It allows for direct comparison and addition.

• It makes the fractions larger.

• It simplifies the fractions.