To go from Joules to kWh you just have to use a simple conversion factor
Rounded to three sig figs, the answer will be
I believe it's appropriate to explain the reasons behind the calculations presented in the first answer.
Let's start from definitions.
Joule (abbreviated as
Watt (abbreviated as
or, in words, one Joule equals to one Watt-second.
Now we have to transform watt and second into kilowatt (
Or, reversing this equality,
Using the above equality, we do the calculations presented in the first answer:
As you see, all the difficulties of this problem lie in the definitions of the units of measurement: the two main ones (