Below is an instruction that describes a task. Write a response that appropriately completes the request in Swahili. Please answer in Swahili.

### Instruction:
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?

### Response:
 Picha hiyo ina ukubwa wa futi 20 kwa 15 = <<20*15=300>>300 futi mraba.
Hivyo inamchukua dakika 300 x 20 = <<300*20=6000>>6000 kupaka rangi kwenye picha hiyo.
Hiyo ni sawa na dakika 6000/60 = <<6000/60=100>>100 saa.
Anatoza $150 kwa saa, hivyo anatoza 100 x 150 = $<<100*150=15000>>15000 kwa kupaka picha hiyo.