Understanding Fractions: Addition and Subtraction

What is the key similarity between adding fractions with the same denominators and adding integers?

• Both require converting to decimals first.

• Both involve simply adding the numerators.

• Both require finding a common denominator.

• Both involve changing the denominators.

Why can't fractions with different denominators be added directly?

• Because they are like adding apples and oranges.

• Because they represent different quantities.

• Because they are like adding apples and watermelons.

• Because they have different numerators.

What is the first step in finding a common denominator for two fractions?

• Subtract the smaller denominator from the larger one.

• Multiply each fraction's denominator by the other fraction's denominator.

• Convert the fractions to decimals.

• Add the numerators together.

When adjusting the numerators after finding a common denominator, what must be done?

• Divide the numerators by the new denominator.

• Multiply the numerators by the same factor as the denominators.

• Add the numerators to the new denominator.

• Subtract the numerators from the new denominator.

In the example of adding one-third and one-half, what is the resulting fraction after finding a common denominator?

• Three-fourths

• Seven-eighths

• Two-fifths

• Five-sixths

What is the common denominator when adding two-fifths and three-sevenths?

• 7

• 10

• 35

• 14

What is the result of adding two-fifths and three-sevenths?

• Twenty-one thirty-fifths

• Thirty thirty-fifths

• Twenty-nine thirty-fifths

• Twenty-five thirty-fifths

In the example of subtracting three-halves and two-thirds, what is the resulting fraction?

• Five-sixths

• One-third

• Seven-eighths

• Two-fifths

What is the common denominator used in the subtraction example of three-halves and two-thirds?

• 2

• 12

• 6

• 3

What will be discussed in the next lecture following this one?

• How to find the least common denominator.

• How to divide fractions.

• How to multiply fractions.

• How to convert fractions to decimals.