In this case, we'll have to carry out several steps to find the solution.
Step 01:
Data
{ 2.8 , -2 3/4 , 3 1/8 , -2.2}
Step 02:
2.8 = 2.8

-2 3/4 = -5 / 4 = - 1.25

3 1/8 = 25 /8 = 3.125
-2.2 = -2.2
Step 03:
from least to greatest
-2.2 < -1.25 < 2.8 < 3.125
The answer is:
{-2.2 , -1.25 , 2.8 , 3.125}
{ -2.2 , - 2 3/4 , 2.8 , 3 1/8 }