Final answer:
The mean of the given set of numbers is 4.08.
Step-by-step explanation:
The mean of a set of numbers is found by adding up all the numbers in the set and then dividing the sum by the total number of values.
For example, to find the mean of the numbers 3.8, 4.2, 4.0, 4.2, 4.2, you would add them up: 3.8 + 4.2 + 4.0 + 4.2 + 4.2 = 20.4. Then, divide the sum by the total number of values, which is 5: 20.4 รท 5 = 4.08. So, the mean of the given numbers is 4.08.