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

### Instruction:
Selena reads a book with 400 pages. Harry reads a book with 20 fewer than half the number of pages Selena's book has. How many pages are in the book of Harry?

### Response:
 Nusu ya idadi ya kurasa za Selena ni 400/2 = <<400/2=200>>200.
20 chini ya nusu ya idadi ya kurasa za kitabu cha Selena ni 200 - 20 = 180.