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

### Instruction:
Greg has his own dog walking business. He charges $20 per dog plus $1 per minute per dog for walking the dog. If he walks one dog for 10 minutes, two dogs for 7 minutes and three dogs for 9 minutes, how much money, in dollars, does he earn?

### Response:
 Ikiwa anatembeza mbwa mmoja kwa dakika 10, anapata 20 + 10 = <<20+10=30>>30 dola.
Ikiwa anatembeza mbwa wawili kwa dakika 7, anapata 2 x (20 + 7) = <<2*(20+7)=54>>54 dola.
Ikiwa anatembeza mbwa watatu kwa dakika 9, anapata 3 x (20 + 9) = <<3*(20+9)=87>>87 dola.
Anapata jumla ya 30 + 54 + 87 = <<30+54+87=171>>171 dola.