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

### Instruction:
My brother and I have thirty minutes to go to school, without being late. It takes us 15 minutes to arrive at the school gate, and another 6 minutes to get to the school building. How much time do we have to get to our room, without being late?

### Response:
 Jumla ya muda tuliotumia kwenda shule ni dakika kumi na tano + dakika sita = <<15+6=21>>21 dakika.
Tunayo dakika thelathini - dakika ishirini na moja = <<30-21=9>>9 dakika zilizobaki ili tusichelewe.