To solve this we are going to use the formula for ideal mechanical advantage:

where

is the machine mechanical advantage

is the input distance

is the output distance
We know for our problem that

and

. Lets replace those values in our formula to find

:



The ideal machine advantage of the machine is 3. The inventor is claiming that the actual mechanical advantage of the machine is 4. Since the actual mechanical advantage takes into account energy losses, it is always less than the ideal mechanical advantage.
We can conclude that the developer's claim is false.