Real-Life LCM Challenges: Find the Least Common Multiple

Anna and Ben are planting flowers. Anna's flowers bloom every 4 weeks, and Ben's flowers bloom every 6 weeks. How many weeks will it take for both of their flowers to bloom together again?

• 16 weeks

• 10 weeks

• 12 weeks

• 8 weeks

A school is planning a field trip. The bus leaves every 15 minutes, and the train leaves every 20 minutes. If they leave at the same time, when will they leave together again?

• 45 minutes

• 60 minutes

• 30 minutes

• 90 minutes

A baker makes cookies in batches of 12 and brownies in batches of 18. If he wants to make the same number of cookies and brownies, what is the least number of each he should make?

• 48

• 30

• 36

• 24

Two friends are playing a game. One friend scores points every 8 seconds, and the other scores every 12 seconds. How long will it take for both friends to score at the same time again?

• 24 seconds

• 20 seconds

• 30 seconds

• 16 seconds

A gardener waters his plants every 10 days, while his neighbor waters hers every 15 days. After how many days will they both water their plants on the same day again?

• 30 days

• 35 days

• 25 days

• 20 days

A music teacher has two classes. One class practices every 5 days, and the other every 7 days. When will both classes practice on the same day again?

• 30 days

• 28 days

• 35 days

• 42 days

A factory produces toys every 9 hours and games every 12 hours. How many hours will pass before both toys and games are produced at the same time?

• 48 hours

• 30 hours

• 24 hours

• 36 hours

A cyclist rides every 14 days, and a runner runs every 21 days. How many days will it take for both to do their activities on the same day again?

• 28

• 35

• 42

• 56

A pet store feeds its cats every 6 hours and its dogs every 8 hours. When will both pets be fed at the same time again?

• 30 hours

• 12 hours

• 18 hours

• 24 hours

Two friends are meeting for lunch. One arrives every 10 minutes, and the other every 15 minutes. If they arrive at the same time, when will they meet again?

• 60 minutes

• 45 minutes

• 15 minutes

• 30 minutes