Find the Common Denominator

What would be the common denominator for adding 3/9 + 4/6?

• 9

• 12

• 18

• 27

What step should you do first when adding fractions with unlike denominators?

• Just add the denominators together

• Find a common denominator

• Add the numerators together first

• Chang each numerator to be the same

What is the least common denominator of 6/8 and 4/12?

• 12

• 24

• 8

• 16

What is the least common denominator of 1/4 and 1/3?

• 4

• 3

• 12

• 8

Which of these numbers could NOT be a common denominator for these two fractions?
2/4   and   3/8

• 32

• 12

• 8

• 24

Which of these numbers could NOT be a common denominator for these two fractions?
1/6   and   1/4

• 12

• 18

• 24

• 36

Which of these numbers could NOT be a common denominator for these three fractions?
1/3   and 2/5   and   3/10

• 15

• 30

• 60

• 90

What do you need to have when adding unlike fractions?

• common denominator

• common numerator

• common numerator and denominator

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

• 3

• 4

• 24

• 12

What is the least common denominator of 1/7 and 3/6?

• 14

• 21

• 7

• 42