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

### Instruction:
Mary is counting the number of minnows in the pond. 40% of the minnows have red bellies, 30% have green bellies and the rest have white bellies. If 20 minnows have red bellies, how many minnows have white bellies?

### Response:
 Idadi ya jumla ya minnows ni minnows 20 / 0.4 = <<20/0.4=50>>50 minnows
Idadi ya minnows kijani ni 30% * minnows 50 = <<30*.01*50=15>>15 minnows
Idadi ya minnows nyekundu au kijani ni minnows 15 + minnows 20 = <<15+20=35>>35 minnows
Idadi ya minnows nyeupe ni minnows 50 - minnows 35 = <<50-35=15>>15 minnows