Formula Syntax Query - Excell 2010

All, I am new to this forum, and Excel and am hoping that someone can provide some guidance on my below query.

I am attempting to use a nested IF statement to deliver a reslt based on multiple conditions. The first 2 IF statements deliver the correct result, however the third IF statement produces a #VALUE! message. Having played with the syntax for a number of hours I am no where nearer to uncovering the error.

=IF(B22<=5,B22*B17,IF(B22<=10,(5*B17)+(B22-5)*C17)),IF(B22<=15,((5*B17)+(5*C17)+(B22-10))*D17)

Attached is a screenshot that displays what I am attempting.

Any assistance would be greatly appreciated.


Best regards