39375

To solve the problem you can't make an omelette you need to test one egg every 5th floor and once that breaks you test the other egg for the number in between e.g. My first egg breaks at the 10th floor I would then have to use my second egg to test floors 6-9. Say that egg breaks on the ninth floor I would then right on the package that it can be dropped from the 8th floor without breaking. Which therefore leaves a maximum test of 24.