Microsoft project rubbish

I attach a dump from the hated Microsoft Project.

This is the start of a plan, i.e. the top line is task #1. Why does project insist on taking tasks which are a round number of days or zero for a milestone and then rolling them up into fractional days? For the two rolled up tasks in the image, one is a whole number of days and the other isn't. Why is this?! All the tasks are using the same standard calendar.

thanks

Craig