To find the mean daily high temperatures for both samples, we'll calculate the average of the temperatures in each sample.
Sample 1:
Daily High Temperatures: 78, 82, 85, 87, 90, 85, 79, 86, 91, 88
Sum of Sample 1 = 78 + 82 + 85 + 87 + 90 + 85 + 79 + 86 + 91 + 88 = 870
Mean of Sample 1 = Sum / Number of Values = 870 / 10 = 87.0
Sample 2:
Daily High Temperatures: 81, 79, 80, 86, 89, 92, 82, 88, 84, 87
Sum of Sample 2 = 81 + 79 + 80 + 86 + 89 + 92 + 82 + 88 + 84 + 87 = 868
Mean of Sample 2 = Sum / Number of Values = 868 / 10 = 86.8
Difference between Mean Daily High Temperatures:
Difference = Mean of Sample 1 - Mean of Sample 2 = 87.0 - 86.8 = 0.2
Thus, the answers are:
The mean daily high temperature of Sample 1 is 87.0 °.
The mean daily high temperature of Sample 2 is 86.8 °.
The mean daily high temperatures of the two samples differ by 0.2 °.