James paints a 20 ft by 15 ft mural.  It takes him 20 minutes to paint 1 square foot and he charges $150 per hour.  How much does he charge to paint the mural?
The mural is 20*15=<<20*15=300>>300 square feet
So it takes him 300*20=<<300*20=6000>>6000 minutes
So he paints it in 6000/60=<<6000/60=100>>100 hours
That means he charges 100*150=$<<100*150=15000>>15000
#### 15000