In this question, since we are talking specifically about the 20 oldest employees, shouldn’t these 20 employees be clearly uniquely identified and not cause overlaps?
When Greg (10:07) takes all employees of the 45-54 range to be 45 years old and all the 55-64 range to be 64 years old to get the maximum range, doesn’t he have 18 guys from the largest age class all tied up, and 21 guys from the second largest age class all tied up, effectively giving 39 oldest employees of the company who cannot be distinguished? Isn’t it better to make all the 18 oldest guys to be 64 y.o., then put 19 guys of the 45-54 group to be 45 y.o and then 2 guys of thus group be 46 y.o. Giving me 20 unique oldest guys in the process? Similarly to find the minimum range but it won’t change the answer of 1 that Greg got
And that’s OK. You are looking for the oldest 20 people. The fact that other people happen to have the same age as some of the people that comprise the oldest 20 does not matter.