Operations of Fractions with Unlike Denominators

What must you do first in order to add or subtract fractions with unlike denominators?

• add the numerators

• add the denominators

• find a common denominator

• find a common numerator

Solve.
(-1/2) + (-5/4)

• -3/4

• 3/4

• 7/4

• -7/4

Which operations with fractions REQUIRE common denominators. Select 2 answers

• Addition

• Subtraction

• Multiplication

• Division

• None of the 4 basic operations

• Add the numerators (top parts of the fractions).

• Rewrite the fractions in the simplest form. 

• Rewrite the fractions with a common denominator. 

• Make each fraction into an improper faction. 

Is this a correct answer?

• Yes, the student correctly added.

• No, you cannot add unlike denominators

• No, 5 + 7 is not 12

• No, 2 + 3 is not 5

Add the fractions:
1/3 + 1/5 =

• 8/15

• 2/5

• 1/2

• 1/3

What must you do first in order to add or subtract unlike fractions?

• add the numerators

• add the denominators

• find a common denominator

• find a common numerator