Not a bad decision, it's really up to your personal interest. There is no right or wrong when it comes to choosing subjects, as long as you are interested, that's all that really matters! Personally, I know a lot of people who did both business and eco, they didn't have any problems with doing both.
I don't do either subject, but I'm fairly sure they have quite different content (maybe some overlap) so I suggest looking at the syllabus and asking teachers or friends about their experience with the subject and a bit about the content to help you make a decision. I think there is a general consensus that business is slightly easier than economics, but again, I don't do the subject so this is just based on what I've heard from friends.
Hope this helps!
I’m in Yr 11 right now and I do Economics. Personally I feel like it is quite an interesting subject and I would do it any day over Business Studies, which everyone says is extremely boring LOL. But again, in the end it is up to what you personally enjoy.
I'm currently doing preliminary economics while doing HSC (accelerated) business studies.
Which is the:
Easiest: business studies
Most interesting: economics
The content can overlap. In my experience it can give you an edge in business on some concepts like economies of scale however this does not mean you will automatically get extra marks. If I were to choose one between them personally I'd choose economics.