What is Ms. Bush’ s main purpose for the trip?

M: Good morning. Can I help you?
W: Hello. My name’s Jill Bush. I’ m planning to go to a conference in Sydney for three weeks.
M: I see. Do you want the excursion fare or the full return fare?
W: Now, can I get a stopover on an excursion fare?
M: Yes, you are allowed only one stopover on the excursion fare.
W: Oh, I see, only one.
M: Yes. But of course, if you pay the full return fare then you can have unlimited stopovers. There’s Singapore, Kuwait, Athens, you’ve really got quite a lot of choices you know.
W: Oh, It sounds good. You see, I’ve got a two-week holiday after the conference. How much is the full fare?
M: The full fare? Well, that’s really quite a lot. It’ s ￡ 1,204.
W; Yes. Well, it’s once in a lifetime, you know. The thing is actually that I’m absolutely afraid of flying. I’ve never done it before.
M: Oh dear. Um...
W: And I’ m hoping that I can persuade my two friends to go along with me.
M: Yes, that would be a good idea.
W: By the way, one of them is in Cairo at the moment. Would it be possible for me to stop over there on my way to Sydney?
M: Yes, of course. There are lots of flights to Cairo and, then plenty more onwards from Cairo to Sydney. And then you can stay for as long as you like.
W: Oh, that’s great! Thanks very much.