Question

On every fourth visit to the hair salon, you receive a discount of $5. On every tenth visit, you receive a free hair product. After how many visits do you receive the discount and a free product at the same time?

Answer 1

To work this out you will need to find the lowest common factor of 4 and 10 since that is when you get there product and discount, therefore the lcm is 20, and therefore that is your answer (20)!