Calculating combinations of animals

@izyat, We are told that a researcher must select 6 animals from among 3 monkeys (F G H), 3 pandas (K L N ), and 3 raccoons (T V Z). The rules tell us that F& H are not both selected, hence we can conclude that at most the researcher could select 2 monkeys. The rules also tell us that N &T are not both selected, so the researcher could not pick 3 pandas and 3 raccoons, meaning he has to pick at least 1 monkey. We can infer two possible scenarios from these rules: (1) One monkey is selected: 1M -2P -3R 1M -3P-2R (2) 2 monkeys are selected (FG) 2M - 3P -1R 2M- 2P- 2R 2M -1P -3R 2 monkeys selected (GH): In this scenario, the rules tell us that K& N must be selected as well, so we must have at least 2P: 2M-2P-2R 2M-3P-1R Let me know if this makes sense and if you have any further questions.