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

### Instruction:
 Katika kopo, kuna mabulinge 7 ya buluu, mabulinge 11 ya nyekundu, na baadhi ya mabulinge ya manjano. Ikiwa nafasi ya kuchagua bulinge la manjano kwa nasibu ni 1/4, kuna mabulinge mangapi ya manjano?


### Response:
 Acha y iwe idadi ya mabulinge ya manjano.
Kuna jumla ya mabulinge 11 + 7 + y = 18 + y.
y/(18 + y) = 1/4.
4y = 18 + y.
3y = 18.
y = <<6=6>>6.
Kuna mabulinge 6 ya manjano.