Is there a way to shorten this formula?

If I enter the formula, IF(AF4+AF5+AF6+AF7+AF8=15,“FULL”) it adds the cell contents and shows FULL. If I write the formula this way, IF(AF4:AF8=15,“FULL”) I get a “#VALUE” error. I was hoping to find out why or if there is a work around.

I am using LibreOffice v. 4.3.7.2
I am using Cacl
I have windows 7 professional and vista home premium

Hallo

IF(SUM(AF4:AF8)=15,"FULL","???")

Thank you to both karolus and Lupp for answering my question. You guys on this forum have been a lot of help.

IF(SUM(AF4:AF8)=15;"FULL") 

will show FULL if the condition is met. But there is no expression to evaluate and to return a value in the alternative case. The IF function will return FALSE (logical value) then as a stopgap. There should better be an alternative like “NOT FULL”.