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Fred has 4 pencils (red, blue, green, and yellow), 3 notebooks (plain, lined, graph), and 9 pieces of chalk (all different colors). He always takes one pencil, one notebook, and one piece of chalk to class.

If he wanted to take a unique combination to class every day, how many days would he be able to do this before he would be forced to repeat one of the combinations?

User GuiDoody
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2 Answers

2 votes
multiply all the numbers, and you will get the answer of 108
User Ozesh
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Around 9 days, because there is a probability of 11% of having a piece of chalk, which is the smallest of the three objects.
User Mikko Maunu
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