In the addition below, all digits have been replaced by letters. Equal letters represent equal digits and different letters represent different digits.
ABCABA
BBDCAA
ABEABB
ABDBAA
------- +
AAFGBDH
What does the complete addition look like in digits?
You and your two friends are working in a multinational company. How can you three find out the average salary of you all without disclosing your own salary to the other two?