Sarah and flora won the science fair. Sarah worked 2 1/3 hours on their project, and flora worked 1/2 hour more than Sarah. How much time did they work altogether?

Sarah worked 1/2 hour more than Flora:

2 1/3 + 1/2 = 2 5/6

The hours worked together:

2 5/6 + 2 1/3 = 5