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

### Instruction:
 James earns $10 per week as an allowance. After saving all his money for four weeks, he spends half of it on a new video game. He then spends a quarter of what is left to buy a new book. How much money does he have left?


### Response:
 Il commence avec $10 * 4 = $<<10*4=40>>40.
James dépense $40 * 1/2 = $<<40*1/2=20>>20 pour le jeu vidéo.
Après avoir acheté le jeu, il lui reste $40 - $20 = $<<40-20=20>>20.
Il dépense $20 * 1/4 = $<<20*1/4=5>>5 pour le livre.
Il lui reste $20 - $5 = $<<20-5=15>>15.