How does a cup with a lid connect the cup with the lid?

Suppose the weight of the cup is x, the weight of the first lid is y, and the weight of the second lid is z,

So Y+X=3Z.

X+Z=4Y，

Then combine two formulas to eliminate z to x = 1 1/4y,

Eliminate y to x = 1 1/5z,

That is, the weight of the cup is 1 1/4 of the first cover and 1 1/5 of the second cover.