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

### Instruction:
 Jack wants to send thank you cards to everyone who got him a gift for his wedding. He sent out 200 invitations. 90% of people RSVPed but only 80% of people who RSVPed actually showed up. Then 10 people who showed up didn't get a gift. How many thank you cards does he need?


### Response:
 90% des personnes ont répondu, soit 200*.90 = <<200*.90=180>>180 personnes.
Ensuite, 80% des personnes qui ont répondu sont venues, soit 180*.80 = <<180*.80=144>>144 personnes.
Ensuite, 10 personnes qui sont venues n'ont pas reçu de cadeau, donc 144-10 = <<144-10=134>>134 personnes lui ont offert un cadeau.
Jack a besoin d'envoyer 134 cartes de remerciement.