( 1)60 *(600-x)+80x & lt; =44000
36000-60x+80x & lt; =44000
20x & lt=8000
X & lt=400 (tree)
You can buy up to 400 B.
(2) If the cost of buying saplings is Y yuan, then y=60*(600-x)+80x.
[0.96 x+0.88 *(600-x)]/600 & gt; =0.9
(0.96 x+528-0.88 x)/600 & gt; =0.9
0.08 x+528 & gt; =540
0.08x & gt= 12
x & gt= 150
y=60*(600-x)+80x
Pack up, take it
y=36000+20x
From this equation (it is best to draw a picture)
When x= 150, the value of y is the smallest.
Y=36000+20* 150, y=39000 (yuan)
A: You should buy 150 seedlings of B and 450 seedlings of A, with a minimum cost of 39,000 yuan.