There are 6 balls in an opaque jar. There are 2 red balls, 2 blue balls, and 2 green balls. What is the minimum I have to take out before I can guarantee I have all of at least one color?
How many license plates can be made using 3 letters A-Z and then 4 numbers 1-9 with repetitions?
Combinations and sampling without replacement (random selection) are investigated. The solution is detailed and well presented. The response was given a rating of "5/5" by the student who originally posted the question.