Average Of 15 And 21

What is the average of 2 numbers : 15 And 21

How to do ?

Let's add these 2 numbers :

15 + 21 = 36

And then to find average, we have to find center point of the summation of these 2 numbers : 36, so let's divide 36 to 2 .

36 / 2 = 18

Answer = 18

Average of 15 and 21 is 18