Final answer:
The mean daily high temperature in Seattle for September converts to 21.11°C, the standard deviation converts to 3.89°C, and the variance is 15.13°C².
Step-by-step explanation:
To convert Seattle's mean daily high temperature in September from Fahrenheit to Celsius, we use the formula °C = (°F - 32) × 5/9. So, the mean temperature in Celsius is (70°F - 32) × 5/9 which equals 21.11°C.
The conversion for standard deviation involves only the ratio part of the conversion factor since standard deviation is a measure of spread and not dependent on the starting point of the scale. The standard deviation in Celsius is 7°F × 5/9, which equals 3.89°C.
To find the variance in Celsius, we square the standard deviation in Celsius (3.89°C), resulting in 15.13°C².