# One way to compare chess-playing programs is to compare how they perform with fixed time limits per move. Given any t...

Kenji on April 28, 2020

more explanation

Could you help explain this question in more detail? Thanks.

Victoria on April 28, 2020

Hi @kenken,

Happy to help!

The passage tells us that you can compare chess-playing programs by examining how they perform with fixed time limits per move.

The passage states that a chess-playing program with fixed time limits placed per move will have a better chance of winning on a faster computer.

Why? Because the extra speed will allow the program to examine more possible moves in the time allotted per move.

We are looking for the answer choice which "must be true" based on the information that we have been provided.

Answer choice (A) is tempting; however, it compares two different programs on the same computer and uses this information to conclude that the program which can examine more moves will have a better chance of winning. The passage compares the same program on computers which run at different speeds. While it is possible that a chess-playing program which can examine more moves will have a better chance of winning, this is not directly supported by the passage as the passage compares the same program run at different speeds.

Answer choice (B) is incorrect because it is irrelevant. The passage is focused on comparing the same program run on different computers. We do not learn anything about the compatibility requirements for different chess-playing programs.

Answer choice (D) is also tempting; however, it compares two different programs on two different computers. We cannot conclude that the program running on the faster computer will be able to examine more moves in the time allotted because we are examining two different programs. It is entirely possible that the program run on the slower computer is more advanced than the program run on the faster computer and, therefore, has the capacity to examine more possible moves in the time allotted despite being run on a slower computer.

Answer choice (E) is incorrect because it is not supported by the passage. We don't know how much extra time would be required on the slower computer to bring it up to the faster computer's capacity. Therefore, we cannot conclude that allotting more time to examine possible moves will necessarily allow the program to have an equal chance of winning on either computer. What if the program only allows for a 50% increase in time but the faster computer runs 60% faster than the slower computer? The slower computer would still be at a disadvantage.

Answer choice (C) is correct because it is directly supported by the passage. The reason the program has a better chance of winning on the faster computer is because it can examine more possible moves in the time allotted. Therefore, the passage supports the statement that the more moves a chess-playing program can examine in the time allotted, the better chance that program has at winning.

Hope this is helpful! Keep up the good work and please let us know if you have any further questions.