What is the smallest three digit number where exactly two digit are the same

100

Step-by-step explanation:

We want to find a number of the form x y z

We want to of the digits to be the same and for it to be as small as possible

For the number to be small, we want x to be 1

1 y z

We can either have y or z be 1 or y = z

If y=z=0 that is smaller than y or z = 1

100

Answer: 100