Person 1 can do a certain job in fifteen minutes, and person 2 can do the same job in thirty minutes. When completing the job together, which expression would be used to represent the amount of work done by person 1?
The expression used to represent the amount of work done by person 1 is 1/15, whereas when it comes to person 2 it is 1/30. You use 1/15 since it is the fifteenth of one hour.