Try it on paper first. A hint, the key idea and the worked solution are here when you need them.
A fair die is rolled times. Find the probability of at least one six.
List all the equally likely pairs and count. For events that do not affect each other, multiply. For at least one, take the chance of none from 1. Without putting back, the second chance changes.
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. No six in one roll. .
Step 2. No six in four rolls. .
Step 3. At least one six. .
Answer: about , a little better than an even chance.
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