2 2/9:y=3 19/27:3 1/320/9:y=100/27:10/320/9:y=100/27*3/1020/9:y=100*3/(27*10)20/9:y=10/9y=20/9:10/9y=20/9*9/10y=2
2 2/9:y=3 19/27:3 1/3
20/9:y=100/27:10/3
20/9:y=100/27*3/10
20/9:y=100*3/(27*10)
20/9:y=10/9
y=20/9:10/9
y=20/9*9/10
y=2