Mastering the Least Common Denominator for Fractions

This video tutorial from Math Tutor DVD explains how to find common denominators for fractions, a crucial skill in math. It covers the process of adding fractions with different denominators, simplifying the results, and extends the concept to algebraic fractions with variables. The tutorial emphasizes the importance of maintaining equivalent fractions by multiplying both the numerator and denominator by the same number.

What is the first rule to remember when adding or subtracting fractions?

• The numerators must be the same.

• The denominators must be the same.

• The fractions must be converted to decimals.

• The fractions must be simplified first.

If you multiply the numerator of a fraction by 3, what must you do to the denominator?

• Divide it by 3.

• Multiply it by 3.

• Add 3 to it.

• Subtract 3 from it.

In the example 3/5 + 1/10, what is the common denominator used?

• 5

• 20

• 15

• 10

What is the simplified form of 8/12?

• 1/2

• 4/6

• 3/4

• 2/3

When adding 2/3 and 1/4, what common denominator is chosen?

• 10

• 8

• 12

• 6

What is the result of adding 1/8 and 1/6 after finding a common denominator?

• 13/24

• 11/24

• 5/24

• 7/24

How do you handle fractions with variables when adding or subtracting?

• Simplify the variables first.

• Convert the variables to numbers.

• Treat the variables as constants and find a common denominator.

• Ignore the variables.

What is the common denominator for the fractions 1/(2x) and 1/x?

• x

• 2x

• 3x

• 4x

What is the simplified form of the fraction 2/y^2 + y/y^2?

• 2 + y/y

• 2 + y/y^2

• 2/y + y

• 2 + y

Why is it important to understand basic fraction rules before learning algebra?

• Because algebra does not involve fractions.

• Because the same rules apply in algebra.

• Because algebra is easier than basic fractions.

• Because algebra uses different rules.