Candy Barr Suzanne Pritchard A Mindtrap Question??????

A mindtrap question?????? - candy barr suzanne pritchard

Dan Manley invited Goodbody Miss Candy Barr and his house for a barbecue. By barbegue Dan is only capable of handeling two hamburgers at the same time, she asked how three burgers cook as quickly as possible. It takes 5 minutes to cook a burger. Therefore, in 10 minutes 2 or boiled, and takes ten minutes to cook hamburgers third. Candy said, that can be boiled three in 15 minutes. How?