Solution:1350x >; = 90xy = c & gt= a/6 =( 1600 x+200000)/6(c & gt； =0)

x & gt=400/ 13

a = 1600 x+200000 & gt； =( 1600*400/ 13)+200000

a & gt=3240000/ 13

a & lt= 6c(c >； =0)

c & gt=540000/ 13

y & lt= 15

The final answer is x=3 1, a=249600, c=4 1850, y= 15.