Which color coat does she finally buy?

M: Good morning! What can I do for you, Madam?
W: Good morning ! I’m looking for a coat.
M: What color would you like?
W: Could you show me some? I’d like a middle sized red coat.
M: Sorry. We haven’t anything in your size.
W: Do you have a smaller size?
M: I’m sorry. The small size coats have just been sold out. What about the blue one? It looks nice and maybe fits you.
W: Well, may I try it on?
M: Yes, please.
W: It seems nice on me. How much is it?
M: 168 yuan.
W: OK. Here is 170 yuan. You keep the change please!
M: Thanks.