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He stole my ball! (Posted on 2019-04-24) Difficulty: 3 of 5
Six balls are at the front of the classroom, and six students are each assigned a different colored ball.

Then they are asked to go up one at a time and take the ball they were assigned.

However, the first student doesn't like the color he was assigned, so he picks randomly from the remaining five.

After that, each successive student takes the color they were assigned if it's available, otherwise they choose randomly from the remaining balls.

What is the probability that the last student gets the ball they were assigned?

No Solution Yet Submitted by Danish Ahmed Khan    
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Some Thoughts related problem | Comment 2 of 8 |
Interestingly, if the 1st student had instead selected completely randomly from all the balls including his own, the last student would have had a 50/50 chance. What I like about this related puzzle, is that there is no computation needed, just logic,  to find the solution, as shown here

Edited on April 25, 2019, 2:35 pm
  Posted by Steven Lord on 2019-04-25 03:34:19

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