The combined mean of the 14 people's index finger is: 12.75 cm.
<h3>How to Find the Combined Mean?</h3>
Combined mean = [(mean of first group × number of data of the first group) + (mean of second group × number of data of the second group)] ÷ (number of data of the first group + number of data of the second group).
Given the following:
Mean of first group = 7.8
Number of data of the first group = 7
Mean of second group = 17.7
Number of data of the second group = 7
Combined mean = [(7.8 × 7) + (17.7 × 7)] / (7 + 7)
Combined mean = 178.5 / 14
Combined mean = 12.75 cm.
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