Answer:
work accomplished = 300*30
= 9,000 J
applied work = 9,000 + 2,000 = 11,000 Joules
efficiency = 100 * work accomplished/work applied
= (9/11)100 = 81.8 %
force applied = (300/6)/.818
= 61.1 N
assuming that the 6 in your question refers to mechanical advantage
He is American. Alex Rodriguez
If you're willing to consider fractions or decimals,
then there are an infinite number of answers.
Like (2.5 x 160), and (15 x 26-2/3).
If you want to stick to only whole numbers,
then these 8 combinations do:
1, 400
2, 200
4, 100
5, 80
8, 50
10, 40
16, 25
20, 20
Gravity pulls the moon towards the earth.