So first you need to by the chain saw and the chipper for $380. It should only take you about 9 hours to assemble it. And lets say that the 31 hours you were looking for the best of the best chain saw and chipper.
344 thousands times 1/10=34,400
Just borrow from the 7 and take the 1 to the 2 and that will make it as 12 so then you subtract 12 - 4 and the answer will be 1,180
The question isn’t clear, can you write it better so I can understand?