Question

CitiBank recorded the number of customers to use a downtown ATM during the noon hour on 32 consecutive workdays. 39 41 25 17 48 29 31 17 24 36 17 24 40 38 42 11 43 47 27 25 17 23 43 20 32 48 26 26 9 46 44 44 Click here for the Excel Data File (a) Find the mean, midrange, geometric mean, and 24 percent trimmed mean. (Round your answers to 2 decimal places.)

Answer 1

Answer:

Mean = 31.22

Midrange = 28.50

Geometric mean = 28.74

Trimmed mean = 31.56

Step-by-step explanation:

Given the data :

39 41 25 17 48 29 31 17 24 36 17 24 40 38 42 11 43 47 27 25 17 23 43 20 32 48 26 26 9 46 44 44

Ordered data :

9, 11, 17, 17, 17, 17, 20, 23, 24, 24, 25, 25, 26, 26, 27, 29, 31, 32, 36, 38, 39, 40, 41, 42, 43, 43, 44, 44, 46, 47, 48, 48

The mean, xbar :

Xbar = Σx / n = 999 / 32 = 31.22

The midrange : (maximum - minimum) / 2

Midrange = (48 + 9) / 2 = 57 / 2 = 28.5

Geometric mean :

(x1*x2*.. xn)^1/n

Geometric mean = (x1*x2*.. xn)^1/32 = 28.74

24% trimmed mean :

24% of 32 = 0.24 * 32 = 7.68 ; this mean cutting off 8 values from the top and bottom and calculating the mean of the remaining values.

Data left :

24, 24, 25, 25, 26, 26, 27, 29, 31, 32, 36, 38, 39, 40, 41, 42

Σx / n = 505 / 16 = 31.5625

Trimmed mean = 31.56