Least Common Multiple Practice

Find the least common multiple of 3 and 9.

• 6

• 9

• 27

• 3

Raya and Santiago are planning a garden and want to create a pattern with flowers that bloom every 5 days and every 7 days. They want to know on which day both flowers will bloom together for the first time.

• 25

• 10

• 42

• 35

Ivan, Evan, and Domenica are planning to build a robot. They need to synchronize two gears, one with 2 teeth and the other with 10 teeth. What is the least number of rotations the 2-tooth gear needs to make for both gears to reach their starting point at the same time?

• 5

• 15

• 20

• 10

Sahil and Safiya are planning to decorate their classroom for a math event. They want to hang ribbons from the ceiling that repeat a pattern every 8 inches for Sahil's design and every 12 inches for Safiya's design. They need to find the shortest length of ribbon that can accommodate both repeating patterns. What is the least common multiple of 8 and 12 inches for the ribbon?

• 24

• 20

• 16

• 10

Calculate the least common multiple of 6 and 9.

• 24

• 3

• 18

• 12

Laszlo and Melanie are planning to run a charity event where they will both sell the same amount of bracelets. If Melanie makes bracelets every 3 days and Laszlo makes bracelets every 5 days, after how many days will they have their first joint sale?

• 8

• 12

• 10

• 15

Find the least common multiple of 4 and 9.

• 27

• 36

• 18

• 12

Domenica and Seiwa are planning a garden and want to create a pattern with rows of tulips and roses. They want to plant tulips every 7 days and roses every 10 days. On which day will they first be able to plant both tulips and roses on the same day?

• 17

• 35

• 42

• 70

What is the least common multiple of 11 and 13?

• 121

• 143

• 33

• 156

Find the least common multiple of 14 and 21.

• 42

• 294

• 63

• 84