I want to travel from Airport CDG to Pasteur (Metro sation) and as far I can tell I will need to take RER B and Metro 6. Here is the plan: http://i.imgur.com/Dam0ziU.png
I was wondering it says "interrupted traffic". Can I still use this way?
Do I need to buy a ticket for RER B and Metro separately? If so, where can I buy tickets?
On my way back I will have travel to Airport Orly: http://i.imgur.com/EkWW5Xy.png
Again, I will have to take the Metro and the RER.
If you're doing this all in one day and need to travel to/from CDG and Orly, then Paris Visite 1-5 zone 1 day ticket will cover everything for you.