=ROUNDUP formula question

[krakurjak]

Thank you for taking the time to read my question. I'm sure it'
something very simple. I am using the ROUNDUP formula, ,but I want i
to round up to .5. For example 23.475 would become 23.5. 10.7542 woul
become 11. 20.000000001 would be 20.5, and so forth. I am medeocre i
my excell knoledge and this seemingly simple formula is beyond me. I d
know that once I see it I will sit back and say "ooooooooohhh yeah
,why didnt I think of that?"

Thank you for your help in advance

 

[JE McGimpsey]

The general formula is

=ROUNDUP(A1*2,0)/2

another way:

=CEILING(A1,0.5)