Addition and Subtraction of Fractions with Unlike Denominators

What is the the next step to finding this answer?

• Add the numerators (1+1=2)

• Multiply 12 X 1 for both fractions to find a new numerator
  

• Multiply to find each new numerator by the multiple used to get 12. (3 X1) (4 X 1)

• This is a mistake, you don't need to convert to twelfths

(Choose one that is true) When you add or subtract fractions with unlike denominators you..

• Add both the numerators and denominators

• Change the denominator by picking a random number then divide

• Find the least common multiple of both denominators

• none of these are true

What must you have to add and subtract fractions?

• Common numerators

• Different numerators

• Different denominators

• Common denominators

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

What is the sum of these fractions in lowest terms?

• 4/5

• 3/20

• 17/20

• 4/20

What is the sum of these fractions?

• 4/5

• 3/20

• 17/20

• 4/20

Solve and simplify if needed:

1/3 - 1/5 =

Mathematical Equivalence

OFF

What is the first step in solving this problem? 
⅘ + ½ =

• Add the top parts of the fraction

• Rewrite the fractions in the simplest form. 

• Find a common denominator. 

• Make each fraction into an improper faction. 

What is the best Common Denominator for the Given Problem?

• 48

• 24

What is the difference of the given problem?

• 
• 
• 
•