Question

The mean length of 9 childrens' big finger is 6.8cm.
The mean length of 3 adults' big finger is 11cm.
What is the mean length (rounded to 2 DP) of these 12 people's big finger?

Answer 1

Answer:

The mean length of these 12 people's big finger is of 7.85 cm.

Step-by-step explanation:

Mean value:

Sum of the values of all observations divided by the number of observations.

In this question:

9 + 3 = 12 total observations

Sum:

$9*6.8 + 3*11 = 94.2$

So

$M = \frac{94.2}{12} = 7.85$

The mean length of these 12 people's big finger is of 7.85 cm.