What is the mean of the data 5, 8, 11, 14, 17, 20?
Arithmetic mean = sum of all observations ÷ number of observations. Here, the sum is 5+8+11+14+17+20 = 75, and there are 6 observations. Thus, the mean is 75/6 = 12.5, so option B is correct. Getting 11.5 would indicate an error in calculating the total or the number of observations. Exam tip: Check both the sum and the total number of observations before dividing.
View question details