To determine which restaurant has more consistent delivery times, we can calculate the standard deviation for each restaurant. A lower standard deviation indicates more consistent delivery times.
For Restaurant 1:
Mean = (40 + 37 + 40 + 41 + 38 + 46 + 41 + 37 + 40 + 40) / 10 = 39.0
Variance = ((40-39)^2 + (37-39)^2 + (40-39)^2 + (41-39)^2 + (38-39)^2 + (46-39)^2 + (41-39)^2 + (37-39)^2 + (40-39)^2 + (40-39)^2) / 10
Variance = (1 + 4 + 1 + 4 + 1 + 49 + 4 + 4 + 1 + 1) / 10 = 269 / 10 = 26.9
Standard Deviation = √26.9 ≈ 5.18
For Restaurant 2:
Mean = (42 + 38 + 37 + 39 + 38 + 40 + 42 + 41 + 40 + 40) / 10 = 39.7
Variance = ((42-39.7)^2 + (38-39.7)^2 + (37-39.7)^2 + (39-39.7)^2 + (38-39.7)^2 + (40-39.7)^2 + (42-39.7)^2 + (41-39.7)^2 + (40-39.7)^2 + (40-39.7)^2) / 10
Variance = (5.29 + 2.89 + 5.29 + 0.09 + 2.89 + 0.09 + 5.29 + 1.69 + 0.09 + 0.09) / 10 = 23.70 / 10 = 2.37
Standard Deviation = √2.37 ≈ 1.54
The standard deviation for Restaurant 1 is approximately 5.18, while the standard deviation for Restaurant 2 is approximately 1.54. Therefore, Restaurant 2 has more consistent delivery times.
The randomly selected delivery times, in minutes, of two restaurants are as follows. Which restaurant has more consistent delivery times?
Restaurant 1 Restaurant 2
40 42
37 38
40 37
41 39
38 38
46 40
41 42
37 41
40 40
1 answer