10x+ 15y=300
8x+ 18y = 300 x = 150y = 100000。
(2) buy a car as a car.
15a+ 10(30-a)≦400
8000A+500A (30A) ≧ 204000A ≧ 18 A ≦ 20A
There are three schemes: Type A 65438 +08 Type B 65438 +02.
A car 19 B car 1 1.
20 vehicles of type A and 0 vehicles of type B 10.