find the landmark in the set of number: 12, 16, 23, 15, 16, 18.

To find the landmark in a set of numbers, you need to determine the smallest and largest values in the set. In this case, the set of numbers is: 12, 16, 23, 15, 16, 18.

Step 1: Arrange the numbers in ascending order:
12, 15, 16, 16, 18, 23

Step 2: Identify the smallest and largest values:
Smallest value: 12
Largest value: 23

So, in this set of numbers, the landmark is 12 (smallest value) and 23 (largest value).