Add and Subtract Unlike Fractions Worded Problems

What is the least common denominator you could use to subtract 1/6 and 1/4?

• 24

• 16

• 20

• 12

Add these fractions.
1/2 + 1/3 =

• 5/6

• 2/5

• 1/5

• 1

Is the problem solved correctly?

• Yes, the student added correctly.

• No, you cannot add unlike denominators

What is the first step in solving this problem?

• Add the numerators (top numbers), then add the denominators (bottom numbers).

• Rewrite the fractions in the simplest form.

• Find the common denominator for each fraction, then make equivalent fractions.

• Change each fraction into improper factions.

Look at the problem. What step is taking place?

• Add the numerators, then add the denominators

• Add the denominators (3 + 4 = 7).

• Simplify the answer

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 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 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

Following the integer rules, would you add or subtract the fractions?

• add, the answer would be positive

• add, the answer would be negative

• subtract, the answer will be positive

• subtract the answer will be negative