Answer :
The mean length of the 15 people's index finger is 15.35 cm.
What is mean?
Mean is the average of a set of numbers. It is determined by adding the numbers together and dividing it by the total number
Mean = sum of the numbers / total number
What is the mean of the 15 people's index finger?
Mean = [(4 x 8.6) + (11 x 17.8)] / 15
(34.4 + 195.8) / 15
230.2 / 15
= 15.35 cm
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