Mastering Addition and Subtraction of Fractions

Professor Dave explains how to add and subtract fractions. He starts with fractions having the same denominator, emphasizing that only numerators are added. He then covers fractions with different denominators, using the least common multiple (LCM) to find a common denominator. Examples include adding one-third and one-fourth, and subtracting one-third from one-fourth. The video also covers more complex operations, like adding one-fifth and two-elevenths, and subtracting two-sevenths from three-fifths. The tutorial concludes with a suggestion for viewers to practice on their own.

What is the result of adding 1/8 and 3/8?

• 4/16

• 4/8

• 1/2

• 3/16

When adding fractions with the same denominator, do we add the denominators?

• Yes, always

• No, only the numerators

• Yes, sometimes

• No, never

What is the least common multiple of 3 and 4?

• 7

• 24

• 12

• 11

How do you convert 1/3 to have a denominator of 12?

• Multiply by 2/2

• Multiply by 4/4

• Multiply by 5/5

• Multiply by 3/3

What is the result of 1/3 minus 1/4 when converted to a common denominator?

• 2/12

• 3/12

• 1/7

• 1/12

What is the least common multiple of 5 and 11?

• 50

• 16

• 55

• 15

After converting 1/5 and 2/11 to a common denominator, what is their sum?

• 21/55

• 13/55

• 23/55

• 12/55

What is the result of 2/7 minus 3/5 when using the least common multiple of 35?

• -11/35

• 11/35

• -10/35

• 10/35

What should you do if fractions have different denominators and you need to add or subtract them?

• Subtract the denominators

• Find the least common multiple

• Add the numerators directly

• Multiply the fractions

Why is it important to practice adding and subtracting fractions?

• All of the above

• To enhance problem-solving skills

• To improve cooking skills

• To prepare for algebra