Question

Midori cleans the hamster cage every 7 days, brushes the dog every 9 days, and cleans the frog aquarium

every 6 days. If Midori does all three today, how many days will pass before Midori takes care of all three of
these pets on the same day again?
​

Answer 1

126

Explanation:

The least common multiple of 7, 9, and 6 is the product of the unique factors.

7 = prime

9 = 3^2

6 = 3·2

The LCM is 7·3^2·2 = 126

Midori will take care of all three pets again after 126 days.