Question

Kevin, Michael and Darren all do their own laundry at home. Kevin does his laundry every 9 days, Michael every 10 days, and Darren every 12 days. If they all did their laundry today, in how many days will the three of them all do their laundry again on the same day

Answer 1

Lowest common multiple of all three numbers = 180 so 180 days

Answer 2

It will be 180 days until they all do laundry on the same day again. I found this by finding the least common multiple of each number.

12 x 15 = 180
10 x 18 = 180
9 x 20 = 180

Hope this helps!