Adding and subtracting fractions with unlike denominators

What is the least common denominator you could use to subtract 1/3 and 1/4?

• 3
• 4
• 24
• 12

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

Solve this equation using the least common denominator.
¼ + ½

• 3/4
• 2/8
• 6/4
• 6/8

What is the least common denominator of 1/2 and 3/7?

• 2
• 14
• 7
• 28

Joe has listed the first 4 multiples of 7 as:

7 14 22 28

Which one is incorrect?

• 7

• 14

• 22

• 28

Solve.
5/9 + 2/9 + 4/9

• 1  2/9
• 5   6/9
• 11/27
• 12/3

A construction company is digging a pit to build the foundation of a house. At the end of the first day, the company had hauled away 1/6 of a truckload of dirt. On the second day, they hauled away 2/6 of a truckload. How many truckloads did they haul away in all?

• 1/4 truckload
• 1/2 truckload
• 3/4 truckload
• 1/3 truckload

1/4 + 5/8

• 2/8
• 6/12
• 3/4
• 7/8