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

### Instruction:
 Tomorrow, Pete must finish paying off the last $90 he owes on a bike. He goes through his wallet and finds two $20 bills. Checking his pockets, he finds four $10 bills. Unhappy that he doesn't have the entire amount, he suddenly remembers that he has plastic bottles that can be returned to his local store for cash. If the store pays 50 cents for each bottle, how many bottles will Pete have to return to the store?


### Response:
 Le portefeuille de Pete contient 2 billets de 20 dollars, soit un total de 2 x 20 = 40 dollars.
L'argent dans les poches de Pete est composé de 4 billets de 10 dollars, soit un total de 4 x 10 = 40 dollars.
Au total, Pete a 40 + 40 = 80 dollars.
Il doit encore 90 - 80 = 10 dollars supplémentaires.
Comme 50 cents équivaut à 1/2 dollar, alors 10 dollars équivaut à 10 x 1/2 = 5 dollars en pièces de 50 cents.
Par conséquent, Pete devra retourner 10 dollars en pièces de 50 cents, ce qui équivaut à 10/0,50 = 20 bouteilles.