Then it will be sufficient to take the arithmetic mean of the two adjustments.
In the construction of such an index number the use of the arithmetic mean is not imperative.
The usual method is to take the arithmetic mean of the values obtained as the correct value.
If, first, we take the arithmetic mean of these limits, we get 117 millions of years.
arithmetic mean a·rith·me·tic mean (ə-rĭth'mĭ-tĭk)
The value obtained by calculating the sum of a set of quantities and then dividing that sum by the number of quantities in the set. Also called average.
The value obtained by dividing the sum of a set of quantities by the number of quantities in the set. For example, if there are three test scores 70, 83, and 90, the arithmetic mean of the scores is their sum (243) divided by the number of scores (3), or 81. See more at mean. Compare average, median, mode.