Answer: The variance of a sample of size n can be calculated using the formula:
variance = (sum of squared deviations from the mean) / (n - 1)
where the deviation from the mean is the difference between each individual value and the sample mean, and the sum of squared deviations is the sum of the squares of these differences.
However, we don't have the individual weights or the sample mean, only the standard deviation. We can use a related formula that expresses the standard deviation in terms of the variance:
standard deviation = sqrt(variance)
Solving for variance, we get:
variance = (standard deviation)^2
Plugging in the given standard deviation of 12.3194 kg, we get:
variance = (12.3194 kg)^2 = 151.8992 kg^2
Therefore, the variance of the weights of the 10 subjects is 151.8992 kg^2.
Explanation: