One major problem is that you're not keeping the units like I showed you.
I think you have everything there, except that I have no idea what that '168'
is all about.
Here it is with the units:
(1million seconds / 1)x(1min/60sec)x(1hr/60min)x(1 day/24hr)x(1 yr/365da)
= (1,000,000 x year) / (60 x 60 x 24 x 365) = 0.03171 year
Except for that screwy mysterious '168', you have everything there,
and in the right place. Again, I'm going to say that you didn't realize
it, because you dropped all the units and suddenly all you saw was a
bunch of numbers in front of you.
