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

### Instruction:
A company hires employees on a contract basis, depending on the availability of work. In a particular month, they hired 200 more employees on the first week than on the second week, and 150 fewer employees on the second week than on the third week. If the number of employees hired on the fourth week was twice the number hired in the third week,  and the number of employees on the fourth week was 400, what's the average number of employees hired per week?

### Response:
 Wiki ya nne ilikuwa na wafanyakazi mara mbili ya wiki ya tatu, kwa hivyo wiki ya tatu ilikuwa na wafanyakazi 400/2 = <<400/2=200>>200.
Katika wiki ya tatu, walimwajiri wafanyakazi 150 wachache kuliko katika wiki ya pili, yaani 200-150 = <<200-150=50>>50 wafanyakazi.
Wiki ya kwanza ilikuwa na wafanyakazi 200 zaidi kuliko wiki ya pili, yaani 50+200 = <<50+200=250>>250 wafanyakazi.
Jumla ya wafanyakazi walioajiriwa ni 250+50+200+400 = <<250+50+200+400=900>>900.
Wastani wa wafanyakazi walioajiriwa kwa wiki ni 900/4 = <<900/4=225>>225 wafanyakazi.