Question

Bridget has swimming lessons every 5th day and diving lessons every third day if she had swimming lesson and a diving lesson on May 5th when will be the next date in which she has both swimming and diving lessons

Answer 1

It'd be May 20th, because you have to the number of days between each time they overlap has to be a number divisible by both 3 and 5, and 15 is the smallest number divisible by both 5 and 3. You add 15 to 5, and get 20, so it's May 20th.