Most people who are skilled banjo players are also skilled guitar players.
Statements
Most skilled banjo are skilled guitar
but
Most skilled guitar are not skilled banjo
Evaluate
We know that correct answers on Inference questions want us to synthesize claims, and we only get two claims here. They have a math-y, quantified feel, so we want to think mathematically.
The famous Most + Most inference that has been tested throughout the years is this: Most A's are B Most A's are C infer: Some B's are C / Some C's are B
But that's not what this is, since the two Most facts are about different groups.
This is a new type of Most + Most inference that has now appeared 2 or 3 times on the last twenty tests. Most A's are B Most B's are ~A infer: There are more B's than A's.
Why is that a valid inference?
A little math helps. Let's say there are 9 skilled banjo players in the world. If we say that most of them are skilled at guitar, then at a minimum we have 5 people who are skilled at banjo and guitar.
So now we get to the fun part: Could we also have 9 skilled guitar players in the world? If so, 5 of them are skilled at banjo and 4 aren't. But that would contradict our statement that "most skilled guitar players aren't good at banjo."
What we have to remember is that the people in this world that are both skilled banjo and skilled guitar are appearing in both of these groups.
When we talk about all the skilled banjo players, we'll be counting these 5 people who are good at banjo and guitar. And when we talk about all the skilled guitar players, we'll be counting these 5 people good at both in that tally as well.
In order for most skilled guitar players to be bad at banjo, we need at least 11 skilled guitar players: 5 are also skilled at banjo, but the majority, the other 6, are not skilled at banjo.
Here it is more graphically:
Just Banjo Banjo and Guitar Just Guitar 4 5 6
9 people are good at banjo. 11 people are good at guitar. 5 people are good at both.
When we say that Most A's are B but Most B's are ~A we're saying that people who are both A and B are a majority of Group A but a minority of Group B.
In our example before, there were 5 people good at both banjo and guitar.
The statements are saying that these 5 people are a majority of the skilled banjo players, so the max total for banjo would be 9.
The statements are saying that these 5 people are a minority of the skilled guitar players, so the min total for guitar would be 11.
if you want to see the other example of this, check out Test 80, Section 1, Q22.
Goal
Look for an answer saying there are more skilled guitarists than skilled banjo players.