27.659, 27.658, 27.657, 27.558
First, to compare each decimal you look at each place. You look at the tens and then ones, tenths, hundredth, and thousandth. They all start with 27, so you look at the tenth place.
27.5
27.6
27.6
27.6
5 is less than 6, so that would go last
Continue going on to the hundredth place with the rest of the numbers.
27.65
27.65
27.65
In the hundredth place, they all have the digit five, so you go on to the thousandth place.
27.657
27.658
27.659
7 is less than 8 or 9, so that goes second to last.
8 is less than 9, so that goes after 27.657 .
9 is the biggest, so that goes first