Answer: 34.5
Explanation:
First, write out all of the numbers from least to greatest.
which is (18,20,26,34,34,35,38,40,42,45)
Second, choose the number in the middle of the set of numbers you wrote out from least to greatest. (There are TWO numbers in this case, which are 34 and 35)
Lastly, since there are two numbers you add them both together and then divide by 2. (34+35=69 , 69 divided by 2 = 34.5)