Group Games Questions - - Question 18

Which one of the following is an acceptable selection of animals for the study?

izyat September 23, 2019

Calculating combinations of animals

How are we able to calculate the different number combination of each type of animal as shown in the explanation (3-2-1), etc?

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Irina October 15, 2019

@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.