what should be added to (1/2 + 1/3 + 1/5) to get 3

what should be added to (1/2 + 1/3 + 1/5) to get 3

what should be added to (1/2 + 1/3 + 1/5) to get 3. There are any references about what should be added to (1/2 + 1/3 + 1/5) to get 3 in here. you can look below.