Question 147
friends of the century $XX$ - Two friends were born in the 20th century, one week apart and in the same month and year. Writing from left to right the date in the form (or the) digit(s) of the day, (or the) digit(s) of the month, and the last two digits of the year, we obtain two numbers, one being the sixth of the other. We didn't put 0 in front of the first 9 months. What is the date of birth of the oldest friend?