MTQ 129 and 140 Bpp kit

Sir in MTQ 129 NB co there is a small thing I want to ask that as we know that for calculating profitability index we divide NPV by initial cost. But in MTQ 129 in solution they are dividing (NPV + initial cost) by initial cost. Can’t we just divide NPV by initial cost?

Similarly in MTQ 140 Guilder co, again in solution they are dividing (NPV + initial cost) by initial cost in order to calculate PI. Can’t we just divide NPV by initial cost?