There are 25 red balls, 47 green balls and 3 blue balls in a basket. There is a blind man. What is the minimum number of balls that the blind man has to pick to make sure that there are at least 2 balls of different colors?

Why this works

This riddle plays on the idea of probability and worst-case scenarios. The key is that the blind man cannot see the colors of the balls, so to ensure he has at least two different colors, we must consider the worst-case scenario where he picks as many balls of one color as possible before getting a different one. Since there are 47 green balls, he could potentially pick all of them first. Therefore, he needs to pick 47 green balls plus one more ball (which could be red or blue) to guarantee he has at least two different colors. Thus, the minimum number of balls he must pick is 48.