Hello!
PE=mgh so if we have a hiker or any object at 200m above ground level and the PE is 117,600J then to find mass we just rearrange the equation for mass, then plug our values in and there we go!
So we get:
PE=mgh
117,600J = m*(9.80m/s^2)*(200m) then solving for m we get
m = 117,600J/(9.80m/s^2)(200m) = 60.0kg
Hope this helps you understand the concept and how to solve!!
Any questions please ask!! Thank you!! :)