Step One is to add up all the values
6.5+5+6+5.5+7+4+4.5+5+6+5.5+4+7.5+6+7+8+5+6+6.5+6.5+5 = 116.5
Step Two is to divide the result from step one by 20 (since there are 20 values added up)
116.5/20 = 5.825
The sample mean is 5.825
Step-by-step explanation:
The answer is 16, all you must do is substitute x with the given value then solve, so 23-7
See attached picture for the answer: