How many times must a man toss a fair com so that the probability of having at least one head is more than 90%?

Explanation

To solve the problem of how many times a man must toss a fair coin so that the probability of getting at least one head is more than 90%, we can follow these steps:

### Step 1: Understand the Probability of Tails
When tossing a fair coin, the probability of getting tails (T) in a single toss is:
\[ P(T) = \frac{1}{2} \]

### Step 2: Calculate the Probability of Getting All Tails
If the coin is tossed \( n \) times, the probability of getting all tails (i.e., no heads) is:
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