Input work & Mechanical advantage.

[pebbles]

Homework Statement

Stan raises a 1200 N piano a distance of 5.00 m with pulleys and pulls on 20 m of rope. What is input work and mechanical advantage?

Homework Equations

Wo=Wi
MA=Fr/Fe

The Attempt at a Solution

I calculated output work as 1200N*5.00m=6.00*10^3 and my book says Wo=Wi; but the answer for input work is 6.80*10^3. I'm not sure what the resistance and effort forces would be. Any help would be appreciated!

 

[pebbles]

i figured out the work input; so the effort force=340N, which i was given in part b of the question. i just need help on the resistance force...

 

[pebbles]

welp. nevermind. i got it. resistance force=1200N duuuh.