Thorny math problem solved

In a story that appeared in the April 24 issues of The Acorn, nine Agoura High School math students were honored for scoring exceptionally well in the recent American High School Math Competition.

To indicate the difficulty of this nationwide competition, we posed to our readers one of the questions that the students had to answer:

An integer between 1000 and 9999, inclusive, is called balanced. If the sum of its two left-most digits equals the sum of its two right-most digits, how many balanced digits are there?

Congratulations to Steven Langberg, a 53-year-old computer programmer from Oak Park, for sending us the correct answer.

Langberg came up with the following formula to reach his conclusion:

Impressive. It’s apparent that Langberg rarely, if ever, skipped math class. And to think that some of the high school juniors and seniors got the answer is even more amazing.

The answer was confirmed by the University of Nebraska, which prepared the test. Agoura High math teacher Tom Beaton relayed the answer to The Acorn.

—John Loesing