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LilScogsy
12-01-2015, 11:20 AM
How often do you have to throw a fair die to have a probability of at least99% to see a number greater or equal 4 at least once?

Subhotosh Khan
12-01-2015, 11:50 AM
How often do you have to throw a fair die to have a probability of at least99% to see a number greater or equal 4 at least once?
What are your thoughts?

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pka
12-01-2015, 04:02 PM
How often do you have to throw a fair die to have a probability of at least99% to see a number greater or equal 4 at least once?
Here is an idea. If one tosses a die ten times, the probability of getting no result greater than 3 is \left(\dfrac{1}{2}\right)^{10}. That is no success, so what is at least one success?

Now how many tries do you need? POST your effort so that we might help you understand.