Answer:
Line up the decimal points. **Answer is Least to greatest: 10.5 , 11, 19**
Explanation:
You need to line each number up.
10.5
11.0
19.0
The reason why 11 and 19 have a decimal point and zero at the end is because you need to do that in order to compare the numbers.
This problem is also a little common sense because 10.5 is the smallest, 19 is the largest while 11 is in the middle.