Question

How long was a 60 W light bulb turned on if it used a total of 580 J of energy?

Answer 1

Here's the tool you need.  You can't answer the question without this:

           "1 watt"
means
           "1 joule of energy, generated, used, or moved, every second".

So      60 watts  =  60 joules per second

           Total energy generated,
            used, or moved                  = (power) x (time).

                                     580 joules  =  (60 watts) x (time)

Divide each side
by  (60 watts):              Time  =  (580 joules) / (60 joules/sec) 

                                               =  (9 and 2/3)  seconds  .