Hello @ all ... i think i wasnt really clear with my question so i made a screenshot of my problem(s)
This cart is infact for a metal recycling/selling comapny where i work in storage and selling.
Goal is to also create inside the ordering system as you see here to let users insert lengths and quantity per lenght for example:
STRIP 100x10 (defaulth lenght = 6.10 meters 6100 mm)
1x 2.00 meters ( or 2000 mm)
1x 3.55 meters ( or 3550 mm)
I wanted to realise that with dhtl +/- for values or with a slider.
unfortumaly i'm not a math hero .. the problem i go encounter with last described situation is that a default lenght is 6.10 meters.
so i need to go figure out how much default lenghts go be required , if someone orders different cuttings...(how much cuttings go fit in to 1 lenght, so i get the required default lenghts i can take out of storage and prepare for cutting)