PL/SQL :: Correlated Update (Inline View)

Can I update inline view like below?

update

(select * from surveys s join answers a on s.survey_id = a.survey_seq_id where month = 201212 and qa = 1 and main_group_id = 55) a,
(select * from surveys s join answers a on s.survey_id = a.survey_seq_id where month = 201212 and qa = 1 and main_group_id = 3) b
where a.survey_id = b.survey_id and substr(a.question_uid , 3) = substr(b.question_uid, 2))

set b.answer = a.answer;

My second question is: The following query is giving error. What can I do?

update answers ans set (ans.answer) = (with a as (select * from surveys s join answers a on s.survey_id = a.survey_seq_id where month = 201212 and qa = 1 and main_group_id = 55),
b as (select * from surveys s join answers a on s.survey_id = a.survey_seq_id where month = 201212 and qa = 1 and main_group_id = 3)
select a.answer from a join b on a.survey_id = b.survey_id and substr(a.question_uid , 3) = substr(b.question_uid, 2) and b.answer_id = ans.answer_id) where ans.main_group_id = 3;

SQL Error: ORA-00904: "ANS"."ANSWER_ID":