You know that light travels 3 x 10⁸ meters every second.
If you knew how many seconds there are in an hour, then
you'd know how many times light traveled 3 x 10⁸ meters,
and you could multiply to find the answer.
So what you really need is the number of seconds in 1 hour.
(1 hour) x (60 minutes/hour) x (60 seconds/minute)
= (1 x 60 x 60) seconds = 3,600 seconds.
In one hour, light travels 3 x 10⁸ meters 3,600 times.
3,600 x 3 x 10⁸ meters = 10,800 x 10⁸
= 1.08 x 10¹² meters .
