When there is a general transformer present, it is quite natural to have resistance in both primary and secondary windings. This resistance that is produced by dual windings can easily be transferred to either of the windings, and the function remains the same in either case. However, if a situation arises wherein, both these resistances are present on a single winding, calculation in this regard is simplified comparatively.
In case there is loss in resistance from one side, another side is balanced in a manner to match up the loss in resistance.
In case of leakage reactance, transference from one end to another is done in the same manner as resistance levels.