Sell products per meter

[Inrhasw]

We are selling product per meter and need to keep track of the inventory.

Like this
We buy a roll in the roll i 550 meter and this we sell per meter.

We have many 10 of this in stock that gives me a total of 5500 meter.

But, i would like to know how many meters I have in the current roll that we are selling from. Ie if I have sold 430 meter on that roll it gives me that I have 120 meter left on that roll, but I have anther 9 rolls to use.

Is this even possible to do?

//B