Where have i gone wrong with this basic mechanics question?

[coffeem]

Homework Statement

[PLAIN]http://img155.imageshack.us/img155/7789/questionz.jpg

The Attempt at a Solution

[PLAIN]http://img826.imageshack.us/img826/1492/myatteptm.jpg

NOTE - it said as an aside it was meant to be 8kg and not 18!

 

[Doc Al]

Redo the arithmetic in the last step, when solving for v.

 

[coffeem]

Redo the arithmetic in the last step, when solving for v.

thanks! does the rest of it look ok?

 

[Doc Al]

does the rest of it look ok?

Yes, it looks fine. My only suggestion is that you be careful about rounding off too soon.