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If a fair coin is tossed 4 times, what is the probability, to the nearest thousandth, of getting exactly 4 heads?

User Aaron Sanders
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Answer: The probability of getting exactly 4 heads in 4 tosses of a fair coin is 0.0625, or 6.25%.

Explanation:

We can use the formula for combinations, which is:

n! / (r! * (n - r)!)

In this case, n is the total number of tosses (4) and r is the number of successes we want to count (4 heads). Plugging these values into the formula, we get:

4! / (4! * (4 - 4)!) = 4! / (4! * 0!) = 4! / (4! * 1) = 1 / 1 = 1

The probability of getting exactly 4 heads in 4 tosses of a fair coin is therefore 1, or 100%. However, this is assuming that the coin is not fair and always lands on heads. If the coin is fair, the probability of getting 4 heads in 4 tosses is actually much lower.

To find the probability of getting 4 heads in 4 tosses of a fair coin, we need to use the formula for binomial probability, which is:

(n! / (r! * (n - r)!) * p^r * (1 - p)^(n - r)

In this case, p is the probability of getting a head in a single toss of the coin (0.5), r is the number of successes we want to count (4 heads), and n is the total number of tosses (4). Plugging these values into the formula, we get:

(4! / (4! * (4 - 4)!) * 0.5^4 * (1 - 0.5)^(4 - 4) = 1 * 0.5^4 * (1 - 0.5)^0 = 0.5^4 * 1 = 0.0625

Thus, the probability of getting exactly 4 heads in 4 tosses of a fair coin is 0.0625, or 6.25%, to the nearest thousandth.

User Billal Begueradj
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