1. If X sets of A-type tables and chairs are produced, then 500-X sets of B-type tables and chairs are produced. According to the meaning of the problem, we can get the inequality group:

2X+3(500-X)≥ 1250

0.5X+0.7(500-X)≤302

Get a solution

240≤X≤250

So there are 1 1 production schemes.

According to the meaning of the question, the relation y = (100+2) x+(120+4) (500-x).

Surface treatment can be carried out.

Y=-22X+62000

Because this is a decreasing function,

So the bigger x, the smaller y,

When x is 250, the cost is minimum.

The cost is y =-22× 250+62000 =-5500+62000 = 56500.