Answer:
The ideal mechanical advantage (IMA) is
.
Explanation:
The ideal mechanical advantage is the ratio of length of longer lever
to that of shorter lever
IMA

Please refer to the image attached.
We could see that the the resistance load moves
cm towards the fulcrum so the distance of resistance load from fulcrum

Now the as the effort force moves
towards the fulcrum overall distance from the fulcrum to the effort force (load)

Plugging the values of the distances in IMA formula we can have.
IMA
.
So the IMA of the fulcrum (simple machine)
