Warehouse A transports 100-x tons to Town B, and warehouse B transports 10+x tons to Town B.
The freight for transportation to Town A is12× 20x+15× (70-x) = 60x+12600.
The freight generated by transportation to Town B is10× 25× (100-x)+8× 20× (10+x) = 25000-250x+1600+/kloc-0.
Total freight y=39200-30x
When the maximum value of x is 70, the freight is the least, y=37 100.
In other words, warehouse A transports 70 tons of rice to town A, 30 tons of rice to town B, and library B transports 80 tons to town B.
2. The most unreasonable mode of transportation is that 70 tons of rice is transported from the second warehouse to Town A, and the rice from the remaining two warehouses is transported to Town B.. The loss caused is 2 100 yuan.