howdy!
to calculate the average of these numbers (19.1, 19.43, and 18.970), you add them together and then divide by the total number of values (which is 3):
(19.1 + 19.43 + 18.970) / 3 = 57.5 / 3 = 19.166666...
rounded to two decimal places, the average is 19.17.