Which one of the following is the maximum number of the six kinds of birds the forest could contain?

Chyanne on January 10, 2021

Please explain this answer choice.

I don't see how more than three birds can be in the forest. The combinations are JMH, MHS, or WGS. When can you have up to four birds?

Replies
Create a free account to read and take part in forum discussions.

Already have an account? log in

shunhe on January 13, 2021

Hi @Chyanne,

Thanks for the question! You can have four birds when you take out W and G. Because remember, if W is in, then H, J, and M can’t be in. So we need to take W out, so leaving W in knocks out three other birds. You also have to take G out, because when you put G in, H can’t be in, and that means M and J again can’t be in. So we take G and W out, and that means we leave J, H, M, and S in. No other rules are contradicted, so this is a valid group, making (C) the correct answer.

Hope this helps! Feel free to ask any other questions that you might have.

Clauzavalet1 on March 12, 2021

How are J,H,M,S in? That would contradict the rule that "when J is out then S is in".

jrb970 on April 1, 2021

No, the rule states that if J/S are out, then S/J are in. The rule does not state that both J and S can be in at the same time. Following the rule, you cannot have both S and J out at the same time.

Mallori on May 12, 2022

That still doesn't make sense to me. How can S and J be in the forest when the last rule states that it's (S or J)?

Emil-Kunkin on May 12, 2022

Hi,

The last rules tells us that if jays are not in the forest then shrikes are. We could diagram this as

If not J - S
and
If not S - J.

In other words, they cannot both NOT be in the forest (or in better words, at least one must be in), but we are not actually told that they cannot both be in together. The rule never tells us "but not both," which is how a rule would state that its either/or.

Rhena on January 19, 2023

Whew! i get it now