Find the value of x .

12.5,-10,-7.5,x ; The mean is 11.5

51

Step-by-step explanation:

The mean is obtained by adding up the values in the data set and then divide by the number of values that you added:

Given our mean as 11.5 and n=4:

#Knowing our sum as 65, we can obtain x by subtracting sum of known values from 65:

Hence, the value of x is 51

yes

step-by-step explanation:

they have to be opposite and reciprocal of eachother.