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

### Instruction:
If I'm 4 times older than Billy currently, and Billy is 4 years old, how old was I when Billy was born?

### Response:
 Kwa sasa, ningekuwa na umri wa 4*4=<<4*4=16>>16 miaka, kwa kuwa mimi ni mara 4 zaidi ya umri wa Billy wa miaka 4.
Kwa hiyo, nilikuwa na umri wa 16-4=<<16-4=12>>12 miaka wakati Billy alipozaliwa.