Question

A binomial experiment has the given number of trials N and the given success probability P.
n= 10, p= 0.3
Determine the probability P(5). Round the answer to at least 3 decimal places.

Answers

Answer
Incorrect
Answer
0.102 is correct
Now (b)Find the mean. Round the answer to two decimal places.
Answer
3.00 is correct.
(c)Find the variance and standard deviation. Round the variance to two decimal places and standard deviation to at least three decimal places.
Answered by GPT-4o mini
To determine the probability \( P(X = k) \) for a binomial distribution, we can use the formula:

\[
P(X = k) = \binom{n}{k} p^k (1 - p)^{n - k}
\]

Where:
- \( n \) = number of trials
- \( k \) = number of successes
- \( p \) = probability of success on each trial
- \( \binom{n}{k} \) = binomial coefficient, calculated as \( \frac{n!}{k!(n-k)!} \)

In this case, we have:
- \( n = 10 \)
- \( k = 5 \)
- \( p = 0.3 \)

Now let's calculate \( P(X = 5) \).

1. Calculate the binomial coefficient \( \binom{10}{5} \):

\[
\binom{10}{5} = \frac{10!}{5!(10-5)!} = \frac{10!}{5!5!} = \frac{10 \times 9 \times 8 \times 7 \times 6}{5 \times 4 \times 3 \times 2 \times 1} = 252
\]

2. Calculate \( p^5 \):

\[
p^5 = (0.3)^5 = 0.00243
\]

3. Calculate \( (1 - p)^{n - k} \):

\[
(1 - p)^{n - k} = (0.7)^{5} = 0.16807
\]

4. Combine all parts to find \( P(X = 5) \):

\[
P(X = 5) = \binom{10}{5} \cdot p^5 \cdot (1 - p)^{5}
\]

\[
P(X = 5) = 252 \cdot 0.00243 \cdot 0.16807
\]

Now multiply these values:

\[
P(X = 5) \approx 252 \cdot 0.00243 \cdot 0.16807 \approx 0.091
\]

Thus, the probability \( P(5) \) rounded to at least three decimal places is:

\[
\boxed{0.091}
\]
Answered by GPT-4o mini
Let's carefully recalculate the probability \( P(X = 5) \) for a binomial distribution with \( n = 10 \) and \( p = 0.3 \).

Using the binomial probability formula:

\[
P(X = k) = \binom{n}{k} p^k (1 - p)^{n - k}
\]

Where:
- \( n = 10 \)
- \( k = 5 \)
- \( p = 0.3 \)
- \( 1 - p = 0.7 \)

1. **Calculate the binomial coefficient \( \binom{10}{5} \)**:

\[
\binom{10}{5} = \frac{10!}{5!5!} = \frac{10 \times 9 \times 8 \times 7 \times 6}{5 \times 4 \times 3 \times 2 \times 1} = 252
\]

2. **Calculate \( p^5 \)**:

\[
p^5 = (0.3)^5 = 0.00243
\]

3. **Calculate \( (1 - p)^{n - k} \)**:

\[
(1 - p)^{n - k} = (0.7)^{5}
\]

Now, calculate \( (0.7)^5 \):

\[
(0.7)^5 = 0.16807
\]

4. **Combine these to find \( P(X = 5) \)**:

\[
P(X = 5) = \binom{10}{5} \cdot (0.3)^5 \cdot (0.7)^{5} = 252 \cdot 0.00243 \cdot 0.16807
\]

Now, calculate the multiplication step-by-step:

- First multiply \( 252 \cdot 0.00243 \):

\[
252 \cdot 0.00243 \approx 0.61176
\]

- Then multiply this result by \( 0.16807 \):

\[
0.61176 \cdot 0.16807 \approx 0.102
\]

Finally, rounding to three decimal places gives:

\[
P(X = 5) \approx 0.102
\]

Thus, the final answer is:

\[
\boxed{0.102}
\]

Thank you for your patience, and I apologize for the previous miscalculation!
Answered by GPT-4o mini
The mean \( \mu \) of a binomial distribution can be calculated using the formula:

\[
\mu = n \cdot p
\]

Where:
- \( n \) is the number of trials,
- \( p \) is the probability of success on each trial.

In this case:
- \( n = 10 \)
- \( p = 0.3 \)

Now we can calculate the mean:

\[
\mu = 10 \cdot 0.3 = 3
\]

Thus, the mean of the binomial distribution, rounded to two decimal places, is:

\[
\boxed{3.00}
\]
Answered by GPT-4o mini
The variance \( \sigma^2 \) of a binomial distribution can be calculated using the formula:

\[
\sigma^2 = n \cdot p \cdot (1 - p)
\]

Where:
- \( n \) is the number of trials,
- \( p \) is the probability of success,
- \( 1 - p \) is the probability of failure.

Given:
- \( n = 10 \)
- \( p = 0.3 \)

Now, we can calculate the variance:

\[
\sigma^2 = 10 \cdot 0.3 \cdot (1 - 0.3) = 10 \cdot 0.3 \cdot 0.7
\]

Calculating it step-by-step:

1. Calculate \( 10 \cdot 0.3 = 3 \).
2. Then calculate \( 3 \cdot 0.7 = 2.1 \).

Thus, the variance is:

\[
\sigma^2 = 2.1
\]

Rounding the variance to two decimal places, we have:

\[
\text{Variance} = \boxed{2.10}
\]

Next, we can find the standard deviation \( \sigma \):

The standard deviation is the square root of the variance:

\[
\sigma = \sqrt{\sigma^2} = \sqrt{2.1}
\]

Calculating \( \sqrt{2.1} \):

\[
\sigma \approx 1.449
\]

Rounding this to at least three decimal places gives:

\[
\text{Standard Deviation} = \boxed{1.449}
\]

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