1. **State the problem:**
We are given a population mean $\mu = 550$ and population standard deviation $\sigma = 75$. We want to find the mean and variance of the sample means for a sample size $n=50$.
2. **Recall the formulas:**
- The mean of the sample means $\mu_x$ is equal to the population mean:
$$\mu_x = \mu$$
- The variance of the sample means $\sigma_x^2$ is the population variance divided by the sample size:
$$\sigma_x^2 = \frac{\sigma^2}{n}$$
3. **Calculate the population variance:**
$$\sigma^2 = 75^2 = 5625$$
4. **Calculate the mean of the sample means:**
$$\mu_x = 550$$
5. **Calculate the variance of the sample means:**
$$\sigma_x^2 = \frac{5625}{50} = 112.5$$
6. **Summary:**
- Mean of sample means $\mu_x = 550$
- Variance of sample means $\sigma_x^2 = 112.5$
These values are rounded to two decimal places as requested.
Sample Means 731C70
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