Answer:
B. The average high temperature in Death Valley was greater than the average in Boise
C. The variation of high temperature in Death valley was about the same as the variation in Boise
Step-by-step explanation:
Step 1: In a normal distribution, about 95% of the values are ±2 standard deviations from the mean. ±2 standard deviation from the mean high temperature of Boise is 39.1 to 65.1. Therefore, option A is wrong
Step 2: The average temperature high temperature of each of the places isngiven by their mean high temperatures.
The mean high temperature in Boise, Idaho, was 52.1°F while the mean high temperature in Death Valley, California, was 81.9°F.
Difference between the mean high temperatures is (81.9 - 52.1) = 29.8°F
Therefore, the average high temperature in Death Valley was greater than the average in Boise. Option B is correct.
Step 3: Standard deviation measures how spread out data is. It is a measure of variation of data.
The standard deviation of the high temperature in Boise, Idaho was 6.5° F, while the standard deviation of the high temperature in Death Valley, California was 6.4° F. This two values are about the same. Therefore, option C is correct.
Step 4: In a normal distribution, about 68% of the values are ±1 standard deviations from the mean. ±1 standard deviation from the mean high temperature of Death Valley is 75.5 to 88.3. Therefore, option D is wrong
Step 5: In a normal distribution, about 99.7% of the values are ±3 standard deviations from the mean. ±3 standard deviation from the mean high temperature of Boise is 32.6 to 71.6. Therefore, option E is wrong
