More force is required to pull the plug in a full bathtub

Solution 28CQ:

Step 1 of 2:-

        First of all we need to understand what Archimedes principle is, because without knowing that, we will not be able to say whether the problem contradicts the principle or not.

        The principle is, the buoyant force on an object is equal to the weight of the liquid displaced by the object.

In our question, it is given that it is easier to pull a plug in an empty bath tub and vice versa.