Adding and Subtracting Fractions: Key Strategies

Dr. Koenig discusses rational number operations, focusing on fractions. The video covers the importance of common denominators in addition and subtraction, converting mixed numbers to improper fractions, and strategies for handling large numbers. The tutorial emphasizes the need for common denominators and provides alternative methods for solving fraction problems, especially when dealing with negatives.

Why is it necessary to have common denominators when adding or subtracting fractions?

• To simplify the fractions

• To make the numerators equal

• To ensure the denominators are the same

• To convert fractions to decimals

What is the common denominator for the fractions 8 and 3?

• 8

• 3

• 16

• 24

When converting a mixed number to an improper fraction, what is the first step?

• Multiply the whole number by the denominator

• Divide the whole number by the numerator

• Add the numerator to the denominator

• Subtract the numerator from the denominator

What is the improper fraction form of 2 1/7?

• 14/7

• 16/7

• 15/7

• 13/7

What is the least common multiple of 7 and 2?

• 2

• 7

• 14

• 21

What should you do after converting mixed numbers to improper fractions?

• Convert them back to mixed numbers

• Simplify the fractions

• Find a common numerator

• Find a common denominator

Why might it be beneficial to keep mixed numbers in their original form when dealing with large numbers?

• To convert them to decimals

• To make the denominators equal

• To simplify the fractions

• To avoid large multiplications

What is the common denominator for the fractions 4 and 9?

• 12

• 36

• 9

• 4

When adding fractions, what remains unchanged?

• The sign

• The whole number

• The denominator

• The numerator

What is the result of adding -10 and -7?

• 17

• -3

• -17

• 3