The probability of a high school basketball team winning any game is [tex]58\%[/tex]. This team is in a six-game tournament, and the games are played independently of one another. Let [tex]X[/tex] represent the number of games the team might win in this tournament.

What are the mean and standard deviation of [tex]X[/tex]?

A. [tex]\mu_x = 2.52, \sigma_x = 2.14[/tex]
B. [tex]u_x = 3.48, \sigma_x = 1.21[/tex]
C. [tex]\mu_x = 3.48, \sigma_x = 1.46[/tex]
D. [tex]\mu_x = 5, \sigma_x = 1.46[/tex]



Answer :

To determine the mean and the standard deviation of the number of games the basketball team might win in a six-game tournament, we must understand that [tex]\(X\)[/tex] follows a binomial distribution. This is because each game has two possible outcomes (win or lose), and the games are played independently.

The parameters for a binomial distribution [tex]\(X\)[/tex] are:
- [tex]\(n\)[/tex]: the number of trials (games), which is 6.
- [tex]\(p\)[/tex]: the probability of success on each trial (probability of winning a game), which is 0.58.

Step 1: Calculate the Mean ([tex]\(\mu_X\)[/tex])

The mean of a binomial distribution [tex]\(X \sim \text{Binomial}(n, p)\)[/tex] is given by:
[tex]\[ \mu_X = n \cdot p \][/tex]

Substitute [tex]\(n = 6\)[/tex] and [tex]\(p = 0.58\)[/tex]:
[tex]\[ \mu_X = 6 \cdot 0.58 = 3.48 \][/tex]

Step 2: Calculate the Standard Deviation ([tex]\(\sigma_X\)[/tex])

The standard deviation of a binomial distribution [tex]\(X \sim \text{Binomial}(n, p)\)[/tex] is given by:
[tex]\[ \sigma_X = \sqrt{n \cdot p \cdot (1-p)} \][/tex]

Substitute [tex]\(n = 6\)[/tex], [tex]\(p = 0.58\)[/tex], and [tex]\(1-p = 1-0.58 = 0.42\)[/tex]:
[tex]\[ \sigma_X = \sqrt{6 \cdot 0.58 \cdot 0.42} \][/tex]

After calculating the above expression:
[tex]\[ \sigma_X \approx 1.21 \][/tex]

So, the mean and standard deviation of [tex]\(X\)[/tex] are:
[tex]\[ \mu_X = 3.48 \quad \text{and} \quad \sigma_X \approx 1.21 \][/tex]

Thus, the correct choice from the given options is:
[tex]\[ \mu_x=3.48, \sigma_x=1.21 \][/tex]