How many hours of DVD or Television content will fit on a 60 gig hard
drive if it is recorded at 12 mbps?

I THINK the answer is 11.38 hours

PS: I thought the maximum video+audio on a DVD was around 9 mbps.

Anyway here's my calculation:
1 megabit = 1048576 bits.

12 megabits per second
12 * 1048576=12582912 bits per second
12582912/8=1572864 bytes per second
1572864/1024=1536 kilobytes per second
1536/1024=1.5 megabytes per second
1.5/1024=.00146484375 gigabytes per second
60/.00146484375=40960 seconds
40960/60=682.666666666666667 minutes
682.66/60=11.3777777777777778 hours

or 11.38 hours rounded to 2 dp

That math looks good, but I see one small flaw in it.  A 60 gig hard
drive does not hold 60 GB.  It really only holds about 55.5 GB. 
Therefore:

55.5/.00146484375=37888 seconds
37888/60=631.4666666666 minutes
631.466/60=10.524444444 hours

So basically about 10.5 hours