add and subtract fractions

What number could be a common denominator for these three fractions?
1/2   and   1/3   and   1/4

• 9
• 8
• 12
• 6

3/4 + 2/8 = 

• 1
• 5/12
• 6/32
• 5/8

5/7 + 1/28 = 

• 6/35
• 12/196
• 21/28
• 1

6/7 - 2/3 =

• 32/21
• 4/21
• 1 3/21
• 7/21

Tim did 1/12 of a load of laundry on Sunday and 1/4 of a load of laundry on Saturday. What fraction of laundry did Tim do in total?

• 2/16 loads done 
• 1/3 loads done 
• 2/3 loads done 
• 2/12 loads done 

Marty made two types of cookies.  He used 2/3 cups of sugar for one recipe and 1/4 cup of sugar for the other.  How much sugar did he use in all?

• 3/7
• 5/12
• 11/12

7/2= what as a mixed number?

• 3  1/2
• 4  3/2
• 4  1/2
• 2  3/2

21/5= what as a mixed number?

• 5  1/5
• 4  2/5
• 4  1/5
• 5  4/5

Simplify  9/45

• 3/15
• 5
• 4
• 1/5

Aiden mowed 1/3 of the lawn and stopped to drink a glass of water. He then mowed 1/6 of the lawn before running out of gas. How much of the lawn did he mow?

Write your answer in its simplest form.

• 1/2

• 3/6

• 1/6

• 2/9