Final answer:
The absolute deviation of 15 in the data set {20, 20, 30, 15, 40} is the absolute value of (15 minus the mean 25), which is 10. So, the correct answer is B. 10.
Step-by-step explanation:
To calculate the absolute deviation of a number in a data set, you subtract the number from the mean of the data set and take the absolute value of the result. The mean of the data set {20, 20, 30, 15, 40} is (20 + 20 + 30 + 15 + 40) / 5, which equals 125 / 5 or 25. The absolute deviation for the number 15 would be the absolute value of (15 - 25), which is the absolute value of -10 or simply 10. Therefore, the correct answer is B. 10.