4x+0.5y+0.4(20-x-y)= 16.3
3.6x+0. 1y+8= 16.3
3.6x+0. 1y=8.3
When x= 1, y=47.
When x=2, y= 1 1.
When x=3, y=-25.
So x=2, y= 1 1, 20-x-y=7.
Answer: There are two coconuts, 1 1 apple and seven oranges.