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

### Instruction:
James has 20 years of experience.  8 years ago John had twice as much experience as James.  Mike started when John had 16 years of experience.  What is their combined experience?

### Response:
 John ana miaka 20+8 = <<20+8=28>>28 ya uzoefu.
Mike ana miaka 28-16 = <<28-16=12>>12 ya uzoefu.
Hivyo, uzoefu wao uliochanganywa ni miaka 28+12 = <<28+12=40>>40.