MathDB

Balls of

3

colours — red, blue and white — are placed in two boxes. If you take out

3

balls from the first box, there would definitely be a blue one among them. If you take out

4

balls from the second box, there would definitely be a red one among them. If you take out any

5

balls (only from the first, only from the second, or from two boxes at the same time), then there would definitely be a white ball among them. Find the greatest possible total number of balls in two boxes.

Problem Statement