Answer: 12
Step-by-step explanation: The mean of a data set is equal to the sum of the set of numbers divided by how many numbers re in the set.
So to find the mean of the data set shown here,
let's begin by adding the numbers.
So we have 12 + 15 + 10 + 11 which is 48.
48 will divided by the number of numbers in the set which is 4.
So we have 48 ÷ 4 which is 12.
So the mean of the data set shown here is 12.