Really interesting question. Here's my take on this.
In each game of a certain tournament, a contestant either loses 3 points or gains 2 points. If Pat had 100 points at the beginning of the tournament, how many games did Pat play in the tournament?
(1) At the end of the tournament, Pat had 104 points
(2) Pat played fewer than 10 games
Let's work with the question stem first.
Equation can be: 100+2w-3l
To find: w+l.
Statement 1:
100+2w-3l= 104
we can make this: 2w+3l=4
2w=4+3l
Since we know the value has to be integral. We can take values. But we can keep the even and odd rule in mind.
We know 4+3l has to be even to be divisible by 2w.
Since, even + even=even. We can infer that 3l is also even. Making l even.
So let's only see values of l which are even: 0,2,4,6,8,10......till infinity.
For l=0, w=2
For l=2, w= 5
For l=4, w= 8
.... There are multiple values resulting in 104 points. Hence, insufficient.
We can remove A and D.
Statement 2: He played less than 10 games.
This is clearly insufficient.
We can remove B
Combining both statements:
As we saw there are multiple versions for his final score, and on adding this filter of less than 2 games, he still would have 2 versions remaining. Making this insufficient.
For l=0, w=2.......He played 2 games
For l=2, w= 5........He played 7 games.
Both leading to a 104 result.
E is the answer.