Question

estimate by rounding to the nearest half

Answer 1

if it's closer to .5, then end it with .5
if it's closer to 0, then end it with 0
examples
closer to .5;
1.3 turns into 1.5
closer 0
8.9 turns into 9
you know when you have to end it with a .5 if the decimal ends with .1 through .4
you know when you have to end it with a .0 if the decimal ends with .5 through .9