What happens to the difference if the decrement is reduced by 3, and 3 is subtracted from the subtracted?

To understand what will happen, let’s equate the diminished X, and the subtracted Y, that is, we get the original expression:

X – Y.

Now let’s do the proposed changes:

(X – 3) – (Y – 3) = X – 3 – Y + 3 = X – 3 – Y + 3 = X – 3.

As you can see, the final expression has come to the initial one. The conclusion can be made as follows: if the reduced and subtracted are changed by an equal number of units (both parts are decreased or increased at the same time), then the total part remains unchanged.