$begingroup$ For (a), an easy way to have a look at is that you've got minimized your likelihood Room to just the mixtures that have at least just one boy: There will be A few other pointers that could be pretty certain to you personally as a singular entity, like- https://girlspggurgaoninsector15.blogspot.com/2025/07/affordable-boys-pg-in-gurgaon-sector-15.html