Factors and multiples

What is the LCM of 90 and 72

• 280

• 420

• 360

• I really do not know?

What's the least common multiple of

5 and 10?

• 50

• 20

• 5

• 10

Find the LCM of 16 and 24.

• 32

• 48

• 64

• 80

If Juanita runs every third day and swims every fifth day, what is the first day that she will both run and swim again? 

• 5
• 15
• 45
• 30

Jenny goes to  karate class every 12 days.and too the library every 18 days. On December 1st she went to both class and the library. On what date will she do both class and go to the library?

• 24 days
• 36 days
• 42 days
• 52 days

What is the short form of least common denominator.

The aquarium offers two types of tours: the Main Tour and the Premium Tour.

Aquarium Tour Times offered

Main Tour Every 30 minutes

Premium Tour Every 45 minutes

How often do these tours start at the same time?

• every 15 minutes

• every 60 minutes

• every 75 minutes

• every 90 minutes

Kevin solved a problem by making these lists:
12: 24, 36, 48, 60
15: 30, 45, 60
Was Kevin trying to find the GCF or LCM of 12 and 15?

• GCF
• LCM

What is the LCM of 21 and 30?

• 420
• 7
• 300
• 210

What is the least common multiple of 5 and 12?

• 10

• 24

• 36

• 60