# Submission: Brainteasers for Warren Buffett's birthday

Warren Edward Buffett is an American business magnate, investor, speaker and philanthropist who serves as the chairman and CEO of Berkshire Hathaway [1]. He is considered one of the most successful investors in the world and has a net worth of US $84 billion, making him the third wealthiest person in the world.

Buffett turns 88 today, and I constructed a fun birthday present for him consisting of some arithmetical brainteaser exercises that I thought he will enjoy going through:

1. Four times the sum of the digits of Buffett’s 88th birthday — expressed as 8/30/2018 — equals 88.

2. If numbers 1 to 26 are assigned to the letters of the English alphabet, the sum of the numbers assigned to Warren’s last name, Buffett, equals 80. And 80 plus its reverse, namely 08, results in 88, too.

3. Further, the sum of the numbers assigned to the letters of Buffett’s first name, Warren, equals 79, and 79 is the 22nd prime number. Four times 22 also gives 88.

4. Moreover, the difference of 8 and 30 — the day and month numbers of Buffett’s birthday — equals 22, and 4 times 22 equals 88 as well.

5. The leftmost three digits of Buffett’s birth year 1930, namely 193, is the 44th prime number, and twice 44 yields 88 too.

6. If the reverse of 1930, namely 0391, is split in the middle as 03 and 91, these two numbers differ by 88.

7. This year has 123 days left following Buffett’s birthday, and twice the sum of the prime factors of 123 — 3 and 41 — equals 88 too.

8. The reverse of Buffett’s birth year, namely 0391, equals 17 times 23. Note that 17 and 23 are the 7th and 9th prime numbers and 7 and 9 are the digits of 79 (Warren).

9. If Buffett’s 88th birthday expressed as 08302018 is split in the middle as 0830 and 2018, the sum of the digits of these two numbers each equal 11, and 11 square plus 11 square equals 242. Interestingly, Buffett’s 88th birthday coincides with the 242nd day of 2018.

10. If Buffett’s birthday, 08301930 is split as 0830 and 1930, the rightmost two digits of these two numbers are each 30 and the difference of the leftmost two digits of each equals 8.

11. Buffett will turn 90 in 2020 on 8/30 and the sum of the prime factors of 830, namely 2, 5, and 83, equals 90.

12. Additionally, Buffett’s 108th birthday expressed as 8/30/2038 will be a full palindrome date.

13. Lastly, if Buffett’s 88th birthday is split as 08, 30, 20 and 18, the sum of 08 and 30, and the sum of 20 and 18 each equals 38. 38 is twice 19, and 19 represents the total number of letters in Warren Edward Buffett.

Aziz Inan is a professor and chair of the electrical engineering program at University of Portland and he can be reached at ainan@up.edu.