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

### Instruction:
 James anapata $10 kwa wiki kama kifuta jasho. Baada ya kuokoa pesa zake kwa wiki nne, anatumia nusu yake kununua mchezo mpya wa video. Kisha anatumia robo ya pesa zilizobaki kununua kitabu kipya. Anabakiwa na pesa kiasi gani?


### Response:
 Ananza na $10 * 4 = $<<10*4=40>>40.
James anatumia $40 / 2 = $<<40/2=20>>20 kwa mchezo wa video.
Baada ya kununua mchezo, anabakiwa na $40 - $20 = $<<40-20=20>>20.
Anatumia $20 / 4 = $5 kununua kitabu.
Anabakiwa na $20 - $5 = $<<20-5=15>>15.