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Assume that the amounts of weight that male college students gain during their freshman year are normally distributed with a mean of μ=1.3 kg and a standard deviation of σ=4.4 kg.

If 16 male college students are randomly selected, find the probability that their mean weight gain during freshman year is between 0 kg and 3 kg.
The probability is _________.

(Round to four decimal places as needed.)

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To find the probability that the mean weight gain of 16 male college students is between 0 kg and 3 kg, we need to use the Central Limit Theorem to approximate the distribution of sample means.

The mean weight gain of 16 male college students will follow a normal distribution with mean μ = 1.3 kg and standard deviation σ/√n, where n is the sample size. In this case, n = 16 and σ = 4.4 kg.

To find the probability, we need to standardize the values using the standard normal distribution.

First, we calculate the standard deviation of the sample mean:

Standard deviation of the sample mean = σ/√n = 4.4/√16 = 1.1 kg

Next, we standardize the values:

Z1 = (0 - μ) / (σ/√n) = (0 - 1.3) / 1.1 = -1.18
Z2 = (3 - μ) / (σ/√n) = (3 - 1.3) / 1.1 = 1.55

Using a standard normal distribution table or a calculator, we can find the probabilities associated with these z-scores:

P(0 kg ≤ X ≤ 3 kg) = P(-1.18 ≤ Z ≤ 1.55)

Consulting the standard normal distribution table, we find that P(Z ≤ -1.18) = 0.1181 and P(Z ≤ 1.55) = 0.9394.

To find the difference between these probabilities, we subtract:

P(-1.18 ≤ Z ≤ 1.55) = P(Z ≤ 1.55) - P(Z ≤ -1.18) = 0.9394 - 0.1181 = 0.8213

Therefore, the probability that the mean weight gain of the 16 male college students is between 0 kg and 3 kg is 0.8213 (rounded to four decimal places).
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