It looks like you're working on a statistics problem that involves determining class midpoints, the sample mean, and possibly the standard deviation from a frequency distribution.

Here's a breakdown of what we see:

• Temperature Classes (°F): 61-64, 65-67, 68-69, 70, 71-72, 73-76, 77-80
• Frequencies: 31, 64, 195, 195, 123, 80, 47
• Class Midpoints (already calculated on the left): 63.0, 66.5, 69.0, 70.5, 72.0, 75.0, 78.5

To calculate the mean of this dataIt looks like you're working on a statistics problem that involves determining class midpoints, the sample mean, and possibly the standard deviation from a frequency distribution.

Here's a breakdown of what we see:

• Temperature Classes (°F): 61-64, 65-67, 68-69, 70, 71-72, 73-76, 77-80
• Frequencies: 31, 64, 195, 195, 123, 80, 47
• Class Midpoints (already calculated on the left): 63.0, 66.5, 69.0, 70.5, 72.0, 75.0, 78.5

To calculate the mean of this

1. Multiply each class midpoint by its respective frequency.
2. Add up these products.
3. Divide the sum by the total number of households (which looks to be 735).

Do you want to proceed with calculating the mean and standard deviation using this method? Let me know if you need help with that!

Here are 5 questions to expand:

1. How do you calculate the class midpoint for a given interval?
2. Why is the frequency distribution important for calculating the mean?
3. What is the formula for standard deviation for grouped data?
4. Can you calculate the cumulative frequency from the data provided?
5. How does the size of the class interval affect the accuracy of the mean and standard deviation?

Tip: When calculating standard deviation for grouped data, remember that it's a measure of how spread out the temperatures are from the mean.