after cutting washer, I put 250 pcs in a box. how can I create the BoM so that it rounds up the box qty when it comes to manufacture?

BoM

   Washer qty=1 Ea

      Sheet metal       qty=10 sq.cm

      Box (250/box)   qty 0.004 box.

Is there any way to set up the UoM, accuracy, precision, bom to always give me a round up in boxes?

example.

MO

Washer Qty needed = 400

   sheet metal  required = 4000sq.cm

   Box (250/box)   required = 2 boxes

(not 1.6 boxes)