11/8 Warmup: Least common denominator

What do you need to have when adding unlike fractions?

• common denominator
• common numerator
• common numerator and denominator

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 Least Common Multiple of 5 and 2?

• 6

• 20

• 10

• 25

What is the least common multiple of 4 and 16?

• 4

• 32

• 16

• 64

What is the least common multiple of 4 and 8?

Mathematical Equivalence

OFF

What is the least common multiple of 6 and 8?

Mathematical Equivalence

ON

Find the LCM of 8 and 10. Work out the problem in your handout and write your answer here.

(a)  

What is the least common denominator for 1/3 and 3/5?

• 15

• 3

• 30

• 10