MathDB

(205) 3

Part of 1989 Tournament Of Towns

Problems(1)

TOT 205 1989 Spring Train J3 888...88?999...99 divisible by 7

Source:

3/7/2021
What digit must be put in place of the "??" in the number 888...88?999...99888...88?999...99 (where the 88 and 99 are each written 5050 times) in order that the resulting number is divisible by 77?
(M . I. Gusarov)
number theorydivisibledividesDigits