Question

Curtis cleans his room every 4 days and cleans his locker every 10 days. If he just cleaned both on the same day, how many days until he cleans both again on the same day?

Answer 1

the first time he cleans his room on the same day is on day 20, since there both 10 and 4 are factors fo 20, then it will take another 20 days for him to clean them on the same day, this will keep repeating,

he will clean both on days 20,40,60,80 and so on...