From the provided image, extract the dialogue and the dialogue's purpose.

Dialogue:

A: What time does the next train from London to Oxford leave?

B: At quarter past one.

A: I'd like one ticket, please.

B: Here you are.

A: How much is it?

B: It's twelve pounds fifty, please.

A: What time does it arrive in Oxford?

B: At half past three.

Purpose: Completing a train ticket with the information from the dialogue.