3-species kinetics problem

At t = 4.0000e-01      y =  9.851641e-01    3.386242e-05    1.480205e-02
At t = 4.0000e+00      y =  9.055097e-01    2.240338e-05    9.446793e-02
At t = 4.0000e+01      y =  7.158016e-01    9.185045e-06    2.841893e-01
At t = 4.0000e+02      y =  4.505207e-01    3.222813e-06    5.494761e-01
At t = 4.0000e+03      y =  1.832269e-01    8.943736e-07    8.167722e-01
At t = 4.0000e+04      y =  3.899012e-02    1.622106e-07    9.610097e-01
At t = 4.0000e+05      y =  4.940021e-03    1.985699e-08    9.950600e-01
At t = 4.0000e+06      y =  5.169551e-04    2.068877e-09    9.994830e-01
At t = 4.0000e+07      y =  5.204938e-05    2.082082e-10    9.999480e-01
At t = 4.0000e+08      y =  5.226977e-06    2.090802e-11    9.999948e-01
At t = 4.0000e+09      y =  5.152617e-07    2.061048e-12    9.999995e-01
At t = 4.0000e+10      y =  4.721229e-08    1.888492e-13    1.000000e+00

Final Statistics.. 

nst = 513    nfe  = 693    nsetups = 100    nje = 11
nni = 690    ncfn = 0      netf = 15