As adverb

??1. I don't expect that as easily, they can solve the problem.

2. They didn't seem to expect that I could solve the cube twice as fast.

3. As easily, one of them could solve the problem.

Are sentences 1,2,3 all correct English?

I think they are, because I learnt that it's possible to omit words before "as adverb" if the omitted words can be guessed by context.

Like "I don't expect that as easily (as others think), they can solve the problem.