Return a blank result from an empty source record

[Brew]

How do I update the following formula so that if c3 is a empty cell, then the result is blank
=IF(OR(C3=0,C3=5),1,IF(OR(C3=1,C3=6),2,IF(OR(C3=2,C3=7),3,IF(OR(C3=3,C3=8),4,IF(OR(C3=4,C3=9),5,"NONE OF THESE")))))

 

[help_questions]

TRY using IF(ISBLANK(.....
OR
IF(ISNULL(...

 

[Fawlty1]

Add: =if(c3="","", to the beginning of the formula

 

[Aladin Akyurek]

=IF(ISNUMBER(C3)*(C3>=0),LOOKUP(IF(C3>=5,C3-5,C3),{0,1;1,2;2,3;3,4;5,"NONE OF 0 to 9"}),"")

 

[Brew]

Great thanks everyone!......Aladin, im using your solution...Thanks again

 

[Brew]

Aladin, i tested your solution and it does go blank, but it doesnt give me the desired result as my original formula:
I have taken out the none of these for 5-9, because it will never occur in my records
=IF(OR(C3=0,C3=5),1,IF(OR(C3=1,C3=6),2,IF(OR(C3=2,C3=7),3,IF(OR(C3=3,C3=8),4,IF(OR(C3=4,C3=9),5))))))
Also, I tried added isblank in this way, but it gives me an () error:
=IF(ISBLANK,(IF(OR(C3=0,C3=5),1,IF(OR(C3=1,C3=6),2,IF(OR(C3=2,C3=7),3,IF(OR(C3=3,C3=8),4,IF(OR(C3=4,C3=9),5))))))

however, Fawlty1's solution gave me the desired result.

 

[Aladin Akyurek]

Aladin, i tested your solution and it does go blank, but it doesnt give me the desired result as my original formula:
...

With which value of C3 doesn't give you the desired result?