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

### Instruction:
 James has 20 pairs of red socks and half as many black socks.  He has twice as many white socks as red and black combined.  How many total socks does he have combined?


### Response:
 Il a 20/2=<<20/2=10>>10 paires de chaussettes noires.
Donc, il a 20+10=<<20+10=30>>30 chaussettes noires et rouges.
Donc, il a 30*2=<<30*2=60>>60 chaussettes blanches.
Donc, il a 60+30=<<60+30=90>>90 chaussettes au total.