One gets some misunderstandings because of it. In this case the balance was only 12 thousand roubles. 37 small and 6 big drums. This way we get one thousand roubles else from Tambov-power. It seems strange but 885 litres of paint is more than 910 and 915.
Point is that a lot of paint are lost because of tint from massive drums to small tare.
The drum with 15 litres can be taken to the maintainable lecture hall and can be used completely. The wrong solution is got not only because of bad methods or bad software, but because of user does not know exactly what he really wants. The purpose is clear when we solve training problems. We remember only optimum plan that can be realized by the software. Nevertheless the excess method in Mathcad will be always the misinterpretation of the first water.