John buys 20 hours of music a month.  The average length of a song is 3 minutes.  He buys each song for $.50.  How much does he pay for music a year?
He buys 20*60=<<20*60=1200>>1200 minutes of music a month
So that is 1200/3=<<1200/3=400>>400 songs
That means he pays 400*.5=$<<400*.5=200>>200 a month
So it comes out to 200*12=$<<200*12=2400>>2400 a year
#### 2400